Radiation Control in Semiconductor Processing

The present disclosure describes a method for controlling radiation conditions and an example system for performing the method. The method includes sending a first setting to configure a radiation device to provide radiation to a substrate undergoing a process operation in a process chamber of the radiation device. The method further includes receiving radiation energy data measured at a plurality of locations of the process chamber and receiving measurement data measured on the substrate during the process operation. The method further includes in response to a variance of the radiation energy data being above a first predetermined threshold and in response to a difference between reference data and the measurement data being above a second predetermined threshold, sending a second setting to configure the radiation device to provide radiation to the substrate.

BACKGROUND

Some semiconductor process operations can be performed in radiation devices. For example, epitaxial growth of silicon (Si) can use halogen lamps as the radiation source. Rapid thermal anneal (RTA) and rapid thermal processing (RTP) can be used to grow oxides or improve doping uniformity. Both RTA and RTP can use halogen lamps as the radiation source. Ultraviolet (UV) lamps can be used as the radiation source to reduce organic contaminants on a wafer. Radiation non-uniformity can increase fabrication complexity and decrease yield.

DETAILED DESCRIPTION

The discussion of elements inFIGS.1-3and5A-8with the same annotations applies to each other, unless mentioned otherwise.

Radiation devices can be used to perform some semiconductor process operations. A radiations device can include a process chamber, where the process operations can be performed, and one or more radiation elements as the radiation source. For example, epitaxial growth of a semiconductor material, such as silicon (Si) and silicon germanium (SiGe), can use halogen lamps as the radiation source. Reactant gases can react in the epitaxy process system to grow the epitaxy utilizing the radiation energy from the halogen lamps. Rapid thermal anneal (RTA) and rapid thermal processing (RTP) can be used to grow oxides or improve doping uniformity. Both RTA and RTP can use halogen lamps as the radiation source. In some embodiments, ambient oxygen can react with a Si substrate in the RTA/RTP process system to form silicon oxide (SiOx) utilizing the radiation energy from the halogen lamps. In some embodiments, ambient oxygen can react with a metal substrate in the RTA/RTP process system to form metal oxide (MOx) utilizing the radiation energy from the halogen lamps. In some embodiments, a protective gas, such as argon (Ar) and nitrogen (N2), can be introduced in the RTA/RTP process system to protect a substrate from oxidation while dopants, such as phosphorous (P) and boron (B), diffuse in the substrate utilizing the radiation energy from the halogen lamps. Ultraviolet (UV) lamps can be used as the radiation source to reduce organic contaminants on a substrate, such as a wafer. The radiation energy from the UV lamps can induce contaminant oxidation on the substrate placed in the UV process system, therefore reducing the amount of organic contaminants on the substrate. Conditions, such as the age of the radiation elements, the resistance of the radiation elements, and the tilt angles of the radiation elements, can affect the radiation energy distribution in the process chamber. Radiation non-uniformity can increase fabrication complexity and decrease yield. Challenges can exist for radiation control in the radiation devices.

The present disclosure is directed to a method for providing radiation control in radiation devices based on radiation energy data and substrate measurement data feedback and an example system for performing the method. A computing device can provide an initial radiation setting to a radiation device. The initial radiation setting can be based on temperature data collected on a test substrate equipped with one or more thermal sensors. The initial radiation setting can be additionally and/or alternatively based on measurement data collected on a test substrate that has completed a process operation of interest. The radiation device can provide radiation to a substrate, such as a production wafer, based on the initial radiation setting. Detection devices can be placed at different locations in the radiation device and collect radiation energy data. One exemplary detection device can include an optical fiber and a photodetector. The computing device can analyze the radiation energy data. If a variance of the radiation energy data is above a predetermined threshold, indicating the radiation energy distribution or non-uniformity is unacceptable, the computing device can adjust the radiation setting and provide the adjusted radiation setting to the radiation device. The radiation device can provide adjusted radiation based on the adjusted radiation setting to the substrate in substantially real time. The radiation device can also provide adjusted radiation based on the adjusted radiation setting to a subsequent substrate, where the subsequent substrate has yet to undergo the process operation. The radiation device can adjust radiation in different ways. For example, an adjustment device can be used to adjust a tilt angle of a radiation element. One exemplary adjustment device can include a motor, such as a stepper motor, a spring, and a lever. In some embodiments, the radiation device can adjust a resistance of a radiation element. In some embodiments, the radiation device can generate an instruction to replace an aged radiation element.

Additionally and/or alternatively, substrate measurement data feedback can be used to control radiation conditions. After the substrate completes the process operation, a measuring device can collect data, such as critical dimension (CD) data, on the substrate. The measurement data can include optical metrology data, optical inspection data, profilometer data, spectrometry data, electrochemical impedance spectroscopy (EIS) data, scanning electron microscopy (SEM) data, transmission electron microscopy (TEM) data, and a combination thereof. In some embodiments, the measurement data can be thickness data of an epitaxial layer on the substrate. In some embodiments, the measurement data can be thickness data of an oxide layer on the substrate. In some embodiments, the measurement data can be dopant concentration data of a doped layer on the substrate. In some embodiments, the measurement data can be contamination percentage data of the substrate. The computing device can analyze the measurement data. If a difference between reference data and the measurement data on the substrate is above another predetermined threshold, also indicating the radiation energy distribution or non-uniformity is unacceptable, the computing device can further adjust the radiation setting and provide the adjusted radiation setting to the radiation device. The radiation device can then provide adjusted radiation based on the further adjusted radiation setting to a subsequent substrate. In some embodiments, the measurement device can collect in-situ data on the substrate, and the radiation device can provide adjusted radiation based on the further adjusted radiation setting to the substrate in substantially real time. In some embodiments, the radiation device can analyze the radiation energy data and the measurement data and adjust the radiation setting itself. The method and example system in the present disclosure can improve radiation distribution and uniformity in substantially real time. The improved radiation uniformity can reduce fabrication complexity, reduce defects, improve yield, and improve device reliability.

According to some embodiments,FIG.1illustrates a diagram of a radiation control system100. Radiation control system100can include a computing device102, a detection device104, an adjustment device106, a radiation device114, and a measuring device116. Radiation device114can include one or more radiation elements108, a process chamber110, and a cooling module112. Radiation control system100can be used to perform radiation control method400, which is described below.

Computing device102can provide radiation settings to configure radiation device114to provide radiation to a substrate. The substrate can be located in process chamber110, such as a on a substrate holder. The radiation settings can be provided to radiation device114by wired and/or wireless means, which can include local area networks (LANs), wide area networks (WANs), the Internet, wireless fidelity (Wi-Fi), Bluetooth, cable, optical fiber, and any combination thereof. Computing device102can receive the radiation energy data detected by one or more detection devices104placed at different locations in process chamber110. Computing device102can receive the measurement data measured by measuring device116on the substrate. The radiation energy data and the measurement data can be provided to computing device102by wired and/or wireless means. Computing device102can analyze the radiation energy data and the measurement data and adjust the radiation settings. In some embodiments, computing device102can feed the radiation energy data and the measurement data into one or more mathematical models, and the mathematical models can adjust the radiation settings based on predetermined constraints and goals. In some embodiments, the mathematical models can be multiple regression analysis models. In some embodiments, the mathematical models can be linear regression models. Based on the adjusted radiation settings, computing device102can send instructions to adjustment device106to adjust a tilt angle or a resistance of radiation element108. The instructions can be sent to adjustment device106by wired and/or wireless means. In some embodiments, computing device102can send instructions to replace an aged radiation element108. The instructions can be displayed on an output means, such as a monitor, of computing device102.

Detection device104can detect radiation energy data, such as in Joules, or temperature data, such as in Celsius, at different locations of radiation device114, and can provide the radiation energy data to computing device102. Detection device104can be installed in radiation device114. Referring toFIG.2, in some embodiments, detection device104can include photodetector202, optical fiber204, and coating layer206. Photodetector202can detect photons and convert photons to a characterization of the radiation energy. In some embodiments, photodetector202can convert photons to an electric current and normalize the electric current as the characterization of the radiation energy. In some embodiments, photodetector202can employ mechanisms, such as photoelectric effect and phonon/heat generation, to characterize the radiation energy. In some embodiments, photodetector202can be a semiconductor-based photodetector, such as a p-n junction.

Optical fiber204can collect photons from its end. Light can be confined in optical fiber based on total internal reflection, and once collected, few photons can escape from optical fiber204. Total internal reflection can ensure that the radiation energy is characterized for the location where the end of optical fiber204is placed. The number of optical fibers204can be between about 3 and about 50. If the number of optical fibers204is below about 3, the radiation energy uniformity data can be non-representative. If the number of optical fibers204is above about 50, the implementation of detection device104can be complicated. In some embodiments, all optical fibers204can connect to one photodetector202. In some embodiments, optical fibers204can be divided into groups, where each group of optical fibers204can connect to one photodetector202. Optical fiber204can withstand a temperature up to about 475 degrees Celsius. In some embodiments, optical fiber204is placed in cooling module112such that cooling module112can protect optical fiber204from high temperature. Each optical fiber204can be replaced if its lifetime has been reached. In some embodiments, optical fiber can be SiOx.

Coating layer206can protect optical fiber204such that detection device104can withstand a higher temperature than without coating layer206. In some embodiments, optical fiber204with coating layer206can withstand a temperature up to about 700 degrees Celsius. Coating layer206can allow detection device104to be used in a greater variety of radiation devices. Coating layer206can be a metal, such as copper (Cu), aluminum (Al), nickel (Ni), gold (Au), and silver (Ag). In some embodiments, detection device104can include additional elements. In some embodiments, detection device104can include thermal sensors.

Referring toFIG.1, adjustment device106can adjust a parameter, such as the tilt angle, of radiation element108. Adjustment device106can receive instructions from computing device102to adjust radiation element108. Adjustment device106can be installed in radiation device114. Referring toFIG.3, in some embodiments, adjustment device106can include motor302, spring304, and lever306. Motor302can be a stepper motor, such as a permanent magnet stepper, a variable reluctance stepper, and a hybrid synchronous stepper. Motor302can have steps per revolution (SPR) between about 4 and about 400. A higher SPR can deliver a more precision adjustment of radiation element108. Spring304can be any suitable spring, such as a compression, extension, torsion, and constant force spring. Spring304can be made of metal. Lever306can be any suitable lever, such as a first class, second class, and third class lever. Lever306can be made of metal or plastic. In some embodiments, adjustment device106can include connection elements, such as screws, rivets, and bolts. In some embodiments, adjustment device106can include additional elements.FIG.3is one exemplary configuration of adjustment device106. In some embodiments, adjustment device106can include more than one motor302, more than one spring304, and more than one lever306. For example, one exemplary adjustment device106can include four motors302, four springs304, and one lever306. In some embodiments, adjustment device106can also have a configuration without a motor, a spring, or a lever to achieve the adjustment function. In some embodiments, adjustment device106can provide a lateral, a vertical, a rotational, or a tilting adjustment to radiation element108. In some embodiments, adjustment device106can adjust other parameters, such as the resistance, of radiation element108.

Referring toFIG.1, radiation device114can include one or more radiation elements108, process chamber110, and cooling module112. Radiation elements can be any suitable radiation source, such as halogen lamps and UV lamps. The number of radiation elements108can be between about 1 and about 100, depending on the predetermined use. Multiple radiation elements108can be arranged in different patterns, such as a line, a triangle, a rectangle, a concentric circle, an ellipse, a diamond, and a trapezoid. Radiation elements108can be connected to adjustment device106such that the tilt angle or the resistance of radiation elements108can be controlled. Radiation elements108can be controlled by other control mechanisms, such as by voltage standby (VSB). VSB can regulate the electrical supplies to radiation elements to adjust the radiation energy output. Radiation device114can also include an electric fan to regulate the process chamber temperature.

Process chamber110can perform a manufacturing process on a substrate placed in the chamber. The manufacturing process can be an anneal process, an oxidation process, an epitaxy process, a deposition process, and an etching process. Process chamber110can include a substrate holder and a mechanism to secure the substrate onto the substrate holder. The mechanism can be a vacuum suction mechanism and a mechanical support mechanism. Process chamber110can include a transfer module or a loading port to receive and return the substrate. The transfer module can deliver the substrate from a substrate carrier to process chamber110and return the substrate to the substrate carrier. In some embodiments, the transfer module can deliver the substrate from process chamber110to measuring device116. The transfer module can be equipped with a robotic arm. The robotic arm can have multiple degrees of freedom. The robotic arm can include a vacuum suction mechanism such that the substrate can be secured on the robotic arm during transfers between different devices. In some embodiments, process chamber110can include a gas supply device and a vacuum pump. The gas supply device can supply process gas, protective gas, and carrier gas to process chamber110. The vacuum pump can extract exhaust gas and maintain a predetermined vacuum level in process chamber110. Process chamber110can include chamber walls, including a top wall, a bottom wall, and sidewalls. Process chamber110can include additional elements.

Cooling module112can reduce overheating of radiation device114. Cooling module112can include a water cooling system and recycled water can absorb excess heat and reduce overheating. Cooling module112can include a cooling system using other liquid or gas coolants. Cooling module112can be a fan. Cooling module112can be integrated in radiation device114at locations where cooling module112can carry away excess heat efficiently. Detection device104can be embedded or encapsulated by cooling module112such that detection device104can sustain a high temperature. In some embodiments, cooling module112can be omitted.

Radiation device114can include exterior chamber walls, including a top wall, a bottom wall, and sidewalls, in addition to the process chamber walls. Radiation device114can include a reflector to concentrate radiation energy emitted by radiation elements108. The reflector can be flat or curved. The reflector can be installed at or near a top wall, a bottom wall, top and bottom walls, or sidewalls of radiation device114or process chamber110. Radiation device114can include radiation window, such as a quartz window. The quartz window can separate radiation elements108from process chamber110. The quartz window can allow radiation energy to emit into process chamber110. The quartz window can be installed at a top portion, a bottom portion, or both top and bottom portions of radiation device114. Radiation device114can include additional elements. Radiation device114can be connected to adjustment device106, detection device104, and measuring device116. Radiation device114can receive the radiation settings from computing device102by wired and/or wireless means. In some embodiments, radiation device114can receive the radiation energy data and the measurement data, analyze the radiation energy data and the measurement data, and adjust the radiation settings itself.

Measuring device116can measure measurement data, such as CD, of structures on a substrate. Measuring device116can be an optical metrology device, an optical inspection device, a profilometer, an EIS, an SEM, a TEM, or other suitable measuring tools. In some embodiments, the measurement can be in-situ or substantially in real time. Measuring device116can include a loading port to receive and return the substrate. In some embodiments, the loading port can receive the substrate from process chamber110and return the substrate to process chamber110. In some embodiments, the loading port can receive the substrate from a substrate carrier and return the substrate to the substrate carrier. One or more sites can be measured across each substrate by measuring device116. Multiple measurement sites can provide CD uniformity information across each substrate. Measuring device116can be a stand-alone device. Measuring device116can transmit the measurement data to computing device102by wired and/or wireless means. Some exemplary measurement data include thickness data of an epitaxial layer on the substrate, thickness data of an oxide layer on the substrate, dopant concentration data of a doped layer on the substrate, and contamination percentage data of the substrate.

Additional devices can be included in radiation control system100and are omitted for simplicity. These additional devices are within the spirit and the scope of this disclosure. Moreover, not all devices may be required to perform the disclosure provided herein.

According to some embodiments,FIG.4is a flow diagram describing a method400for controlling radiation conditions.FIGS.5A-7Cillustrate various applications of radiation control method400, in accordance with some embodiments. For ease of description, method400will be described first. In each application, the operations illustrated inFIG.4will be referred to and method400will be described for the various applications illustrated inFIGS.5A-7C. Additional operations can be performed between the various operations of method400and are omitted for simplicity. These additional operations are within the spirit and the scope of this disclosure. Moreover, not all operations may be required to perform the disclosure provided herein. Additionally, some of the operations can be performed simultaneously or in a different order than the ones shown inFIG.4. Method400can be performed by radiation control system100, in accordance with some embodiments.

Referring toFIG.4, in operation402, a radiation setting can be provided to configure a radiation device to provide radiation to a substrate undergoing a process operation in a process chamber of the radiation device. For example, the radiation setting can be provided by computing device102ofFIG.1. In some embodiments, the radiation setting can be provided by radiation device114. The radiation setting can be provided to radiation device114to configure radiation device114to provide radiation to the substrate in process chamber110. The radiation can be provided by radiation elements108. The radiation setting can include a number of radiation elements108to be turned on, a level of heat (e.g., low, medium, and high) to be provided by radiation elements108, a resistance of radiation elements108, a tilt angle of radiation elements108, and whether to employ cooling module112. The radiation setting can depend on the various applications, such as the various applications illustrated inFIGS.5A-7C.

Referring toFIG.4, in operation404, radiation energy data can be collected at one or more locations of the process chamber. For example, detection device104can be placed at different locations of process chamber110. Detection device104can detect radiation energy data at the different locations. Detection device104can transmit the radiation energy data to computing device102or radiation device114. In some embodiments, measurement data can be collected on the substrate. For example, measuring device116can measure data, such as CD data, on the substrate. The measurement can be in-situ and substantially in real time. The measurement can also be after the substrate completes the process operation in process chamber110. Measuring device116can transmit the measurement data to computing device102or radiation device114. The radiation energy data and the measurement data can be received by computing device102or radiation device114and analyzed by computing device102or radiation device114. The radiation energy data can be energy data in Joules, or temperature data in Celsius, depending on the type of detection device104. The radiation energy requirement can depend on the various radiation device setups, such as the various radiation device setups illustrated inFIGS.5A-7C. The measurement data can include optical metrology data, optical inspection data, profilometer data, EIS data, SEM data, and/or TEM data. The measurement data can depend on the various applications, such as the various applications illustrated inFIGS.5A-7C.

Referring toFIG.4, in operation406, a determination can be made whether a variance of the radiation energy data is above a predetermined threshold. In some embodiments, the radiation energy should be uniform across process chamber110. A variance of the radiation energy data can then be obtained by comparing the radiation energy data to the average or to reference energy data. In some embodiments, the radiation energy can be based on a distribution. For example, the radiation energy can be high in the center of process chamber110and low at the edges of process chamber110. A variance of the radiation energy data can then be obtained by comparing the radiation energy data to reference energy data for each location. The determination whether the variance of the radiation energy data is above the predetermined threshold can be made by computing device102. If the variance is below the predetermined threshold, the same radiation setting can be provided to radiation device114. In other words, operation402can be performed. In some embodiments, another determination based on the measurement data can be made, which is described below in operation408, before the same radiation setting can be provided to radiation device114. In response to the variance being above the predetermined threshold, computing device102or radiation device114can adjust the radiation setting based on the radiation energy data and method400can continue to operation410. The predetermined threshold can depend on the various applications, such as the various applications illustrated inFIGS.5A-7C.

Referring toFIG.4, in operation408, a determination can be made whether the difference between reference data and the measurement data is above a predetermined threshold. In some embodiments, the measurement should be uniform across the substrate. The difference can then be obtained by comparing the measurement data to one reference data. In some embodiments, the measurement can be based on a distribution. For example, the measurement can be high in the center of the substrate and low on the edges of the substrate, or the measurement can conform to a function, such as a sinusoidal, linear, and exponential function. A difference can then be obtained by comparing the measurement data to reference data for each measurement site on the substrate or each data point on a reference curve. The determination whether the difference between the reference data and the measurement data is above the predetermined threshold can be made by computing device102or radiation device114. If the difference is below the predetermined threshold, the same radiation setting can be provided to radiation device114. In other words, operation402can be performed. In response to the difference being above the predetermined threshold, computing device102or radiation device114can adjust the radiation setting based on the measurement data and method400can continue to operation410. The predetermined threshold can depend on the various applications, such as the various applications illustrated inFIGS.5A-7C.

Referring toFIG.4, in operation410, an adjusted radiation setting can be provided to configure the radiation device to provide adjusted radiation to the substrate. In some embodiments, the adjusted radiation setting can be provided to configure the radiation device to provide adjusted radiation to a different substrate that has yet to undergo the process operation. For example, the adjusted radiation setting can be provided by computing device102or radiation device114. The adjusted radiation can be provided by radiation device114to process chamber110. The process operation can be performed in process chamber110. Based on the radiation energy data and the measurement data, computing device102or radiation device114can adjust the number of radiation elements108to be turned on, the level of heat (e.g., low, medium, and high) to be provided by radiation elements108, the resistance of radiation elements108, the tilt angle of radiation elements108, and whether to employ cooling module112. The adjusted radiation setting and the adjusted radiation conditions can depend on the various applications, such as the various applications illustrated inFIGS.5A-7C. The adjusted radiation setting can assist in optimizing the radiation conditions in process chamber110and in achieving the measurement data within a predetermined range. If the radiation conditions are not optimized or if the measurement data remains outside the predetermined range, further adjustments can be made to the radiation settings. Because the radiation energy data and the measurement data can be monitored and fed into the radiation settings constantly or periodically, radiation conditions in process chamber110can be controlled to yield the measurement data within the predetermined range. The radiation energy data can also facilitate replacing aged radiation elements108. Radiation control method400and radiation control system100can improve yield and quality.

FIGS.5A-7Cillustrate various applications of radiation control method400, in accordance with some embodiments.FIGS.5A-5Eillustrate an epitaxy process system and an application where radiation conditions are controlled to achieve desired epitaxy thicknesses.FIGS.6A and6Billustrate a UV process system and an application where radiation conditions are controlled to reduce contamination.FIGS.7A-7Cillustrate an RTA/RTP process system and two applications. The first application is where radiation conditions are controlled to achieve a desired oxide thickness. The second application is where radiation conditions are controlled to achieve desired dopant concentrations. The operations illustrated inFIG.4will be referred to and method400will be described for each application. The discussion of elements inFIGS.1-3and5A-8with the same annotations applies to each other, unless mentioned otherwise.

FIGS.5A-5Eillustrate an epitaxy process system and an application where radiation conditions are controlled to achieve desired epitaxy thicknesses.FIG.5Aillustrates an epitaxy process system500. Epitaxy process system500can include radiation device chamber walls530, radiation elements108, cooling module112, and reflectors510. Radiation elements108can be halogen lamps. Epitaxy process system500can include process chamber110, a substrate holder502, and a substrate holder support504. A substrate506, such as a wafer, can be secured on substrate holder502by a mechanism, such as a vacuum suction mechanism. Substrate506can be a semiconductor material, such as Si, germanium (Ge), SiGe, a silicon-on-insulator (SOI) structure, and/or a combination thereof. Further, substrate506can be doped with p-type dopants, such as B, indium (In), aluminum (Al), and gallium (Ga), or n-type dopants, such as P and arsenic (As). Precursor gases508can be used to epitaxially grow an epitaxial layer, such as Si and SiGe, on substrate506. For example, the epitaxial Si layer can be grown using source gases, such as silane (SiH4), silicon tetrachloride (SiCl4), trichlorosilane (TCS), and dichlorosilane (SiH2Cl2or DSC). Hydrogen (H2) can be used as a reactant gas to reduce the aforementioned source gases. The growth temperature during the epitaxial growth can range from about 700° C. to about 1250° C. depending on the gases used. For example, source gases with fewer chlorine atoms (e.g., like DSC) can require lower formation temperatures compared to source gases with more chlorine atoms, such as SiCl4or TCS. Radiation control can be important in growing a uniform epitaxial layer. If the radiation is not uniform, epitaxial layer can be non-uniform. If the radiation is too strong, epitaxial layer thickness can be too great. If the radiation is too weak, epitaxial layer thickness can be too small. A detection device including photodetector202, optic fiber204, and coating layer206can be used to detect radiation energy at different locations in process chamber110. Even thoughFIG.5Aillustrates the detection device on the top portion of epitaxy process system500, another detection device can be installed on the bottom portion of epitaxy process system500.

FIG.5Billustrates an arrangement of radiation elements108.FIG.5Billustrates radiation elements108can be arranged in a concentric circle. The concentric circle of radiation elements108can be placed at both the top and bottom portions of epitaxy process system500.FIG.5Billustrates22radiation elements but the number of radiation elements108can be between about 1 and about 100. Not every radiation element needs to be turned on to provide radiation. In some embodiments, a portion of radiation elements108needs to be turned on to provide a predetermined level of radiation energy. The tilt angles of radiation elements108can be adjusted to control radiation energy distribution. Not all radiation elements108are adjusted at one time to provide radiation control, in accordance with some embodiments. In some embodiments, tilt angles of a portion of radiation elements108are adjusted. For example, tilt angles of 8 out of the 22 radiation elements inFIG.5Bare adjusted, in accordance to some embodiments.

FIG.5Cillustrates an epitaxial layer on a substrate. For example, epitaxial layer514can be grown on substrate506. Substrate506can be a semiconductor material, such as Si and SiGe. Substrate506can include structures, such as fin structures. Epitaxial layer514can be epitaxially grown with suitable precursor gases, and epitaxial layer514can be a semiconductor material, such as Si and SiGe. Thickness of epitaxial layer514can be between about 1 nm and 100 nm.FIG.5Dillustrates measurement data compared to reference data across a substrate. For example, as shown by reference data516, thickness of epitaxial layer514can be smaller near the center of substrate506than near the edges of substrate506. Measurement data518can show actual data measured on substrate506after substrate506completes the epitaxy process operation or during the epitaxial growth. There can be a difference between measurement data518and reference data516. The difference can be caused by radiation non-uniformity. The difference can be used to feedback to radiation settings to control radiation. After the radiation settings are optimized, measurement data518should substantially overlap with reference data516. In other words, the difference between reference data516and measurement data518should be below a predetermined threshold.FIG.5Dillustrates one exemplary functional representation of reference data516. In some embodiments, reference data516can correspond to other functional representations, such as a linear, a parabolic, a sinusoidal, and an exponential function.

FIG.5Eillustrates a test substrate with thermal sensors. The initial radiation setting provided by computing device102can be determined based on historical empirical data, such as historical equipment setup data, historical equipment monitoring data, historical equipment health data, and historical measurement data. In some embodiments, a test substrate can be used to ascertain the initial conditions of the radiation device. In some embodiments, a test substrate can be similar to a production substrate. The test substrate can undergo the process operation and measurement data collected on the test substrate can be used to determine the initial radiation setting.FIG.5Eillustrates a test substrate with thermal sensors, in accordance with some embodiments. Test substrate506can be equipped with one or more thermal sensors522and one or more wires524. Thermal sensors522can measure temperature data at different locations of substrate holder502. Wires524can transmit the temperature data to computing device102for analysis. Based on the temperature data, computing device102can provide the initial radiation setting. In some embodiments, thermal sensors522can be bonded to substrate506. In some embodiments, thermal sensors522can be a thermally-sensitive material sputtered on substrate506. The test wafer can include other sensors.

In applying method400to the application illustrated byFIGS.5A-5E, referring toFIG.4, in operation402, a radiation setting can be provided by computing device102to configure epitaxy process system500to provide radiation to substrate506undergoing the epitaxy process. In some embodiments, the radiation setting can be provided by epitaxy process system500. The epitaxy process can be performed in process chamber110. Substrate506can be secured on substrate holder502. The radiation can be provided by radiation elements108. Reflectors510can enhance the radiation in process chamber110. The radiation setting can include a number of radiation elements108to be turned on, a level of heat (e.g., low, medium, and high) to be provided by radiation elements108, a resistance of radiation elements108, a tilt angle of radiation elements108, and whether to employ cooling module112.

Referring toFIG.4, in operation404, radiation energy data can be collected by detection device104at one or more locations in process chamber110. Ends of optical fiber204can detect radiation energy data at the different locations. In some embodiments, optical fiber204can be embedded in cooling module112such that optical fiber204can be protected from overheating. The radiation energy data can be transmitted to computing device102or epitaxy process system500. In some embodiments, measurement data can be collected on substrate506. Referring toFIG.5C, thickness of epitaxial layer514can be measured by measuring device116, such as an optical spectrometer. The measurement can be in-situ and substantially in real time. The measurement can also be after substrate506completes the epitaxy process in process chamber110. Measuring device116can transmit the measurement data to computing device102or epitaxy process system500. The radiation energy data and the measurement data can be received by computing device102or epitaxy process system500and analyzed by computing device102or epitaxy process system500. The radiation energy data can be energy data in Joules, or temperature data in Celsius, depending on the mechanism of photodetector202.

Referring toFIG.4, in operation406, a determination can be made whether a variance of the radiation energy data is above a predetermined threshold. The radiation energy should be uniform across process chamber110. A variance of the radiation energy data can then be obtained by comparing the radiation energy data to the average or to reference energy data. The determination whether the variance of the radiation energy data is above the predetermined threshold can be made by computing device102or epitaxy process system500. If the variance is below the predetermined threshold, the same radiation setting can be provided to epitaxy process system500. In other words, operation402can be performed. In some embodiments, another determination based on the measurement data can be made, which is described below in operation408, before the same radiation setting can be provided to epitaxy process system500. In response to the variance being above the predetermined threshold, computing device102or epitaxy process system500can adjust the radiation setting based on the radiation energy data and method400can continue to operation410.

Referring toFIG.4, in operation408, a determination can be made whether the difference between reference data and the measurement data is above a predetermined threshold. Referring toFIG.5D, the reference data can be plotted as reference data516across the substrate, and the actual measurement data can be plotted as measurement data518across the substrate. The difference can then be obtained by comparing measurement data518to reference data516for each measurement site on the substrate. The determination whether the difference between reference data516and measurement data518is above the predetermined threshold can be made by computing device102or epitaxy process system500. If the difference is below the predetermined threshold, the same radiation setting can be provided to epitaxy process system500. In other words, operation402can be performed. In response to the difference being above the predetermined threshold, computing device102or epitaxy process system500can adjust the radiation setting based on measurement data518and method400can continue to operation410.

Referring toFIG.4, in operation410, an adjusted radiation setting can be provided by computing device102or epitaxy process system500to configure epitaxy process system500to provide adjusted radiation to the substrate. In some embodiments, the adjusted radiation setting can be provided to configure epitaxy process system500to provide adjusted radiation to a different substrate that has yet to undergo the epitaxy process operation. The adjusted radiation can be provided by radiation elements108to process chamber110. The epitaxy process operation can be performed in process chamber110. Based on measurement data518and the radiation energy data, computing device102or epitaxy process system500can adjust the number of radiation elements108to be turned on, the level of heat (e.g., low, medium, and high) to be provided by radiation elements108, the resistance of radiation elements108, the tilt angle of radiation elements108, and whether to employ cooling module112. The adjusted radiation setting can assist in optimizing the radiation conditions in process chamber110and in achieving the epitaxial layer thickness within a predetermined range. If the radiation conditions are not optimized or if the epitaxial layer thickness remains outside the predetermined range, further adjustments can be made to the radiation settings. Because the radiation energy data and the measurement data can be monitored and fed into the radiation settings constantly or periodically, radiation conditions in process chamber110can be controlled to yield the epitaxial layer thickness within the predetermined range. The radiation energy data can also facilitate replacing aged radiation elements108. Radiation control method400and radiation control system100can improve yield and quality for the epitaxy process operation. The radiation energy data feedback can be substantially in real time. The epitaxial layer thickness data feedback can be substantially in real time because optical spectrometry can measure the thickness data in-situ and non-destructively. In some embodiments, the epitaxial layer thickness data feedback can be after the substrate completes the epitaxy process operation.

FIGS.6A and6Billustrate a UV process system and an application where radiation conditions are controlled to reduce contamination.FIG.6Aillustrates a UV process system600. UV process system600can include radiation device chamber walls530, radiation elements108, reflectors510, and a radiation window614. Radiation elements108can be in an elongated shape, for example, along radiation window614. Radiation window614can be made of a material that is transparent or translucent, such as quartz. Radiation window614can separate radiation elements108from process chamber110and allow light/radiation to pass through. UV process system600can include process chamber110, substrate holder502, and substrate holder support504. UV process system600can include a gas supply608, a pump612, and gas pipes and/or conduits610. Gas supply608can supply a process gas or a protective gas to process chamber110via gas pipes and/or conduits610. Pump612can be a gas transfer pump or an entrapment pump. Pump612can extract exhaust gases from process chamber110via gas pipes and/or conduits610. Pump612can provide a vacuum condition to process chamber110for some applications. Substrate506can be secured on substrate holder502by a mechanism, such as a vacuum suction mechanism. Substrate506can be a wafer and can have semiconductor structures on it. UV light can be used to oxidize organic contaminants and reduce surface contamination on substrate506. Radiation control can be important in reducing contamination, such as organic contaminants, on substrate506. If the radiation is non-uniform, surface cleaning can be non-uniform and some areas of substrate506can have too much contamination. If the radiation is too strong, the UV light can damage some semiconductor structures on substrate506. If the radiation is too weak, the surface cleaning can be insufficient. The surface cleaning is insufficient if, for example, the percentage of contamination on substrate506after UV process is above a predetermined threshold. A detection device including photodetector202, optic fiber204, and coating layer206can be used to detect radiation energy at different locations in UV process system600. Even thoughFIG.6Aillustrates the detection device on the top portion of UV process system600, another detection device can be installed on the bottom portion of UV process system600.

FIG.6Billustrates contaminants on a substrate. For example, contaminants620can be found on substrate506. Contaminants can be from the cleanroom environment, from a cleaning process operation, from an etching process operation, from a deposition process operation, and from a photolithography process operation. Substrate506can have semiconductor structures of small sizes, and the semiconductor structures can be damaged by the weight of contaminants620. Contaminants620can also prevent the semiconductor structures from a next process operation, further causing defects and reducing yield. Contamination can be quantified by inspecting the total number of contaminants620or inspecting the total number of the semiconductor structures affected by contaminants620. A percentage of the contamination can then be calculated by comparing the total number of the semiconductor structures affected by contaminants620with the total number of the semiconductor structures on substrate506. There can be a difference between the percentage of the contamination and a predetermined threshold. The difference can be caused by radiation non-uniformity. The difference can be used to feedback to radiation settings to control radiation. After the radiation settings are optimized, the percentage of the contamination should be at and/or below the predetermined threshold.

In applying method400to the application illustrated byFIGS.6A and6B, referring toFIG.4, in operation402, a radiation setting can be provided by computing device102to configure UV process system600to provide radiation to substrate506undergoing the surface cleaning process. In some embodiments, the radiation setting can be provided by UV process system600. The surface cleaning process can be performed in process chamber110. Substrate506can be secured on substrate holder502. The radiation can be provided by radiation elements108. Reflectors510can enhance the radiation in process chamber110. The radiation can pass through radiation window614. The radiation setting can include a number of radiation elements108to be turned on, a level of heat (e.g., low, medium, and high) to be provided by radiation elements108, and whether an aged radiation element108need to be replaced. The initial radiation setting can be based on historical equipment data, historical measurement data, and data obtained from a test substrate with thermal sensors.

Referring toFIG.4, in operation404, radiation energy data can be collected by detection device104at one or more locations in UV process system600. Ends of optical fiber204can detect radiation energy data at the different locations. The radiation energy data can be transmitted to computing device102or UV process system600. In some embodiments, inspection data can be collected on substrate506. The percentage of the contamination can be inspected by measuring device116, such as an optical inspection metrology tool. In some embodiments, a camera or a microscopy can be placed in process chamber110such that the inspection can be in-situ and substantially in real time. The inspection can also be after substrate506completes the surface cleaning process in process chamber110. Measuring device116can transmit the inspection data to computing device102or UV process system600. The radiation energy data and the inspection data can be received by computing device102or UV process system600and analyzed by computing device102or UV process system600. The radiation energy data can be energy data in Joules, or temperature data in Celsius, depending on the mechanism of photodetector202.

Referring toFIG.4, in operation406, a determination can be made whether a variance of the radiation energy data is above a predetermined threshold. The radiation energy should be uniform across process chamber110. A variance of the radiation energy data can then be obtained by comparing the radiation energy data to the average or to reference energy data. The determination whether the variance of the radiation energy data is above the predetermined threshold can be made by computing device102or UV process system600. If the variance is below the predetermined threshold, the same radiation setting can be provided to UV process system600. In other words, operation402can be performed. In some embodiments, another determination based on the inspection data can be made, which is described below in operation408, before the same radiation setting can be provided to UV process system600. In response to the variance being above the predetermined threshold, computing device102or UV process system600can adjust the radiation setting based on the radiation energy data and method400can continue to operation410.

Referring toFIG.4, in operation408, a determination can be made whether the percentage of the contamination is above a predetermined threshold. Referring toFIG.6B, the percentage of the contamination can be calculated by comparing the total number of the semiconductor structures affected by contaminants620with the total number of the semiconductor structures on substrate506. The determination whether the percentage of the contamination is above the predetermined threshold can be made by computing device102or UV process system600. If the percentage of the contamination is below the predetermined threshold, the same radiation setting can be provided to UV process system600. In other words, operation402can be performed. In response to the percentage of the contamination being above the predetermined threshold, computing device102or UV process system600can adjust the radiation setting based on the inspection data and method400can continue to operation410.

Referring toFIG.4, in operation410, an adjusted radiation setting can be provided by computing device102or UV process system600to configure UV process system600to provide adjusted radiation to the substrate. In some embodiments, the adjusted radiation setting can be provided to configure UV process system600to provide adjusted radiation to a different substrate that has yet to undergo the surface cleaning process operation. The adjusted radiation can be provided by radiation elements108to process chamber110. The surface cleaning process operation can be performed in process chamber110. Based on the radiation energy data and the inspection data, computing device102or UV process system600can adjust the number of radiation elements108to be turned on, the level of heat (e.g., low, medium, and high) to be provided by radiation elements108, and whether to send an instruction to replace an aged radiation element108. The adjusted radiation setting can assist in optimizing the radiation conditions in process chamber110and in achieving the percentage of the contamination below a predetermined threshold. If the radiation conditions are not optimized or if the percentage of the contamination remains above the predetermined range, further adjustments can be made to the radiation settings. Because the radiation energy data and the inspection data can be monitored and fed into the radiation settings constantly or periodically, radiation conditions in process chamber110can be controlled to yield the percentage of the contamination below a predetermined threshold. The radiation energy data can also facilitate replacing aged radiation elements108. Radiation control method400and radiation control system100can improve yield and quality for the surface cleaning process operation. The radiation energy data feedback can be substantially in real time. In some embodiments, the percentage of the contamination data feedback can be after the substrate completes the surface cleaning process operation.

FIGS.7A-7Cillustrate an RTA/RTP process system and two applications. The first application is where radiation conditions are controlled to achieve a desired oxide thickness, as shown inFIG.7B. The second application is where radiation conditions are controlled to achieve desired dopant concentrations, as shown inFIG.7C.FIG.7Aillustrates an RTA/RTP process system700. RTA/RTP process system700can include radiation device chamber walls530, radiation elements108, reflectors510, and radiation window614. Radiation elements108can be halogen lamps. Radiation elements108can be embedded in cooling module112, each radiation element108having its own slot. Each of the top portion and the bottom portion of RTA/RTP process system700can have a set of radiation elements108, radiation window614, and reflector510. RTA/RTP process system700can include process chamber110, a substrate support702, and an edge ring704. Substrate506, such as a wafer, can be secured on substrate support702by the physical constraint of edge ring704. A detection device including photodetector202, optic fiber204, and coating layer206can be used to detect radiation energy at different locations in RTA/RTP process system700. Each optic fiber204can be placed in a slot with each radiation element108. Each optic fiber204can then detect the radiation energy around each radiation element108. Optic fiber204can also be protected from overheating by cooling module112. Even thoughFIG.7Aillustrates the detection device on the top portion of RTA/RTP process system700, another detection device can be installed on the bottom portion of RTA/RTP process system700. RTA/RTP process system700can also include a thermal sensor710, such as a pyrometer.

FIG.7Billustrates an application where radiation conditions are controlled to achieve a desired oxide thickness. Material layer712can be a semiconductor material, such as Si, Ge, and SiGe, and oxide layer714can be SiOx, germanium oxide (GeOx), and silicon germanium oxide (SiGeOx). Material layer712can be a metal, such as Cu, cobalt (Co), a transition metal, and Al, and oxide layer714can be a metal oxide. In some embodiments, material layer712can be a material that needs to be oxidized by RTA/RTP process system700, and oxide layer714can be an oxide layer corresponding to the oxidized material layer712. Material layer712can be formed on substrate506. RTA/RTP process system700can oxidize material layer712in ambient air or with an oxygen gas flow. The temperature during the oxide layer growth can range from about 200° C. to about 1300° C. Radiation control can be important in growing a uniform oxide layer. If the radiation is not uniform, oxide layer can be non-uniform. If the radiation is too strong, oxide layer thickness can be too great. If the radiation is too weak, oxide layer thickness can be too small. Thickness of oxide layer714can be between about 1 nm and 500 nm. There can be a difference between measurement data and reference data for the oxide layer thickness. The difference can be caused by radiation non-uniformity. The difference can be used to feedback to radiation settings to control radiation. After the radiation settings are optimized, the measurement data for the oxide layer thickness should overlap with the reference data. In other words, the difference between the reference data and the measurement data should be below a predetermined threshold.

In applying method400to the application illustrated byFIG.7B, referring toFIG.4, in operation402, a radiation setting can be provided by computing device102to configure RTA/RTP process system700to provide radiation to material layer712undergoing the oxidation process. In some embodiments, the radiation setting can be provided by RTA/RTP process system700. The oxidation process can be performed in process chamber110. Material layer712can be formed on substrate506, and substrate506can be secured on substrate support702by the physical constraint of edge ring704. The radiation can be provided by radiation elements108. Reflectors510can enhance the radiation in process chamber110. The radiation can pass through radiation window614. The radiation setting can include a number of radiation elements108to be turned on, a level of heat (e.g., low, medium, and high) to be provided by radiation elements108, a resistance of radiation elements108, whether to employ cooling module112, and whether to send an instruction to replace an aged radiation element108. The initial radiation setting can be based on historical equipment data, historical measurement data, and data obtained from a test substrate with thermal sensors.

Referring toFIG.4, in operation404, radiation energy data can be collected by detection device104at one or more locations in RTA/RTP process system700. Ends of optical fiber204can detect radiation energy data at the different locations. In some embodiments, optical fiber204can be embedded in cooling module112such that optical fiber204can be protected from overheating. In some embodiments, each optical fiber204can be placed in a slot where each radiation element108is located. The radiation energy data can be transmitted to computing device102or RTA/RTP process system700. In some embodiments, measurement data can be collected on substrate506. Referring toFIG.7B, thickness of oxide layer714can be measured by measuring device116, such as an optical spectrometer. The measurement can be in-situ and substantially in real time. The measurement can also be after material layer714completes the oxidation process in process chamber110. Measuring device116can transmit the measurement data to computing device102or RTA/RTP process system700. The radiation energy data and the measurement data can be received by computing device102or RTA/RTP process system700and analyzed by computing device102or RTA/RTP process system700. The radiation energy data can be energy data in Joules, or temperature data in Celsius, depending on the mechanism of photodetector202.

Referring toFIG.4, in operation406, a determination can be made whether a variance of the radiation energy data is above a predetermined threshold. The radiation energy should be uniform across process chamber110. A variance of the radiation energy data can then be obtained by comparing the radiation energy data to the average or to reference energy data. The determination whether the variance of the radiation energy data is above the predetermined threshold can be made by computing device102or RTA/RTP process system700. If the variance is below the predetermined threshold, the same radiation setting can be provided to RTA/RTP process system700. In other words, operation402can be performed. In some embodiments, another determination based on the measurement data can be made, which is described below in operation408, before the same radiation setting can be provided to RTA/RTP process system700. In response to the variance being above the predetermined threshold, computing device102or RTA/RTP process system700can adjust the radiation setting based on the radiation energy data and method400can continue to operation410.

Referring toFIG.4, in operation408, a determination can be made whether the difference between reference data and the measurement data is above a predetermined threshold. Referring toFIG.7B, oxide layer714can be desired to be uniform, and reference data can be determined. The actual measurement data of the thickness of oxide layer714can be measured by measuring device116. The difference between the actual measurement data and the reference data can then be obtained by comparing the measurement data to the reference data for each measurement site on the substrate. The determination whether the difference between the reference data and the measurement data is above the predetermined threshold can be made by computing device102or RTA/RTP process system700. If the difference is below the predetermined threshold, the same radiation setting can be provided to RTA/RTP process system700. In other words, operation402can be performed. In response to the difference being above the predetermined threshold, computing device102or RTA/RTP process system700can adjust the radiation setting based on the measurement data and method400can continue to operation410.

Referring toFIG.4, in operation410, an adjusted radiation setting can be provided by computing device102or RTA/RTP process system700to configure RTA/RTP process system700to provide adjusted radiation to the substrate. In some embodiments, the adjusted radiation setting can be provided to configure RTA/RTP process system700to provide adjusted radiation to a different substrate that has yet to undergo the epitaxy process operation. The adjusted radiation can be provided by radiation elements108to process chamber110. The oxidation process operation can be performed in process chamber110. Based on the radiation energy data and the measurement data, computing device102or RTA/RTP process system700can adjust the number of radiation elements108to be turned on, the level of heat (e.g., low, medium, and high) to be provided by radiation elements108, the resistance of radiation elements108, and whether to employ cooling module112. The adjusted radiation setting can assist in optimizing the radiation conditions in process chamber110and in achieving the oxide layer thickness within a predetermined range. If the radiation conditions are not optimized or if the oxide layer thickness remains outside the predetermined range, further adjustments can be made to the radiation settings. Because the radiation energy data and the measurement data can be monitored and fed into the radiation settings constantly or periodically, radiation conditions in process chamber110can be controlled to yield the oxide layer thickness within the predetermined range. The radiation energy data can also facilitate replacing aged radiation elements108. Radiation control method400and radiation control system100can improve yield and quality for the oxidation process operation. The radiation energy data feedback can be substantially in real time. The oxide layer thickness data feedback can be substantially in real time because optical spectrometry can measure the thickness data in-situ and non-destructively. In some embodiments, the oxide layer thickness data feedback can be after the substrate completes the oxidation process operation.

FIG.7Cillustrates another application where radiation conditions are controlled to achieve desired dopant concentrations. Intrinsic layer716can be a semiconductor material, such as Si, Ge, and SiGe. Doped layers718and720can be formed by doping intrinsic layer716with p-type dopants, such as B, In, Al, and Ga, or n-type dopants, such as P and As. Doped layers718and720can have different dopant concentrations. For example, doped layer720can have a dopant concentration between about 1×1020atoms/cm3and about 1×1021atoms/cm3. Doped layer718can have a dopant concentration between about 1×1020atoms/cm3and about 3×1022atoms/cm3. The difference in the dopant concentrations can be caused by the dopant implantation process operation. Intrinsic layer716and doped layers718and720can be formed on substrate506. RTA/RTP process system700can anneal the doped layers718and720to redistribute the dopants such that the dopant concentration is uniform across doped layers718and720. In some embodiments, a protective gas can be supplied to process chamber110to prevent oxidation during anneal. The temperature during anneal can range from about 200° C. to about 1300° C. Radiation control can be important in a post-implantation anneal to generate a uniform dopant concentration. If the radiation is not uniform, the dopant distribution can be non-uniform. If the radiation is too strong, the dopants can diffuse too far below the surface and the dopant concentration near the surface can be too low. If the radiation is too weak, the energy can be insufficient to drive the dopants to diffuse and the dopant distribution can be non-uniform. The dopant concentration of doped layers718and720can be about 1×1020atoms/cm3and about 3×1022atoms/cm3after anneal. There can be a difference between the measured dopant concentration and reference data for the dopant concentration. The difference can be caused by radiation non-uniformity. The difference can be used to feedback to radiation settings to control radiation. After the radiation settings are optimized, the measured concentration should be substantially similar to the reference concentration. In other words, the difference between the reference data and the measurement data should be below a predetermined threshold.

In applying method400to the application illustrated byFIG.7C, referring toFIG.4, in operation402, a radiation setting can be provided by computing device102to configure RTA/RTP process system700to provide radiation to doped layers718and720undergoing the post-implantation anneal process. In some embodiments, the radiation setting can be provided by RTA/RTP process system700. The post-implantation anneal process can be performed in process chamber110. Intrinsic layer716and doped layers718and720can be formed on substrate506, and substrate506can be secured on substrate support702by the physical constraint of edge ring704. The radiation can be provided by radiation elements108. Reflectors510can enhance the radiation in process chamber110. The radiation can pass through radiation window614. The radiation setting can include a number of radiation elements108to be turned on, a level of heat (e.g., low, medium, and high) to be provided by radiation elements108, a resistance of radiation elements108, whether to employ cooling module112, and whether to send an instruction to replace an aged radiation element108. The initial radiation setting can be based on historical equipment data, historical measurement data, and data obtained from a test substrate with thermal sensors.

Referring toFIG.4, in operation404, radiation energy data can be collected by detection device104at one or more locations in RTA/RTP process system700. Ends of optical fiber204can detect radiation energy data at the different locations. In some embodiments, optical fiber204can be embedded in cooling module112such that optical fiber204can be protected from overheating. In some embodiments, each optical fiber204can be placed in a slot where each radiation element108is located. The radiation energy data can be transmitted to computing device102or RTA/RTP process system700. In some embodiments, measurement data can be collected on substrate506. Referring toFIG.7C, dopant concentrations of doped layers718and720can be measured by measuring device116, such as an EIS. The measurement can be in-situ and substantially in real time. The measurement can also be after substrate506completes the post-implantation anneal process in process chamber110. Measuring device116can transmit the measurement data to computing device102or RTA/RTP process system700. The radiation energy data and the measurement data can be received by computing device102or RTA/RTP process system700and analyzed by computing device102or RTA/RTP process system700. The radiation energy data can be energy data in Joules, or temperature data in Celsius, depending on the mechanism of photodetector202.

Referring toFIG.4, in operation406, a determination can be made whether a variance of the radiation energy data is above a predetermined threshold. The radiation energy should be uniform across process chamber110. A variance of the radiation energy data can then be obtained by comparing the radiation energy data to the average or to reference energy data. The determination whether the variance of the radiation energy data is above the predetermined threshold can be made by computing device102or RTA/RTP process system700. If the variance is below the predetermined threshold, the same radiation setting can be provided to RTA/RTP process system700. In other words, operation402can be performed. In some embodiments, another determination based on the measurement data can be made, which is described below in operation408, before the same radiation setting can be provided to RTA/RTP process system700. In response to the variance being above the predetermined threshold, computing device102or RTA/RTP process system700can adjust the radiation setting based on the radiation energy data and method400can continue to operation410.

Referring toFIG.4, in operation408, a determination can be made whether the difference between a reference concentration and the measured concentration is above a predetermined threshold. Referring toFIG.7C, the dopant concentration in doped layers718and720can be desired to be uniform, and the reference concentration can be determined. The actual measurement data of the dopant concentrations of doped layers718and720can be measured by measuring device116. The difference between the actual dopant concentration and the reference concentration can then be obtained by comparing the measured concentration to the reference concentration for each measurement site on the substrate. The determination whether the difference between the reference concentration and the measured concentration is above the predetermined threshold can be made by computing device102or RTA/RTP process system700. If the difference is below the predetermined threshold, the same radiation setting can be provided to RTA/RTP process system700. In other words, operation402can be performed. In response to the difference being above the predetermined threshold, computing device102or RTA/RTP process system700can adjust the radiation setting based on the measured concentration and method400can continue to operation410.

Referring toFIG.4, in operation410, an adjusted radiation setting can be provided by computing device102or RTA/RTP process system700to configure RTA/RTP process system700to provide adjusted radiation to the substrate. In some embodiments, the adjusted radiation setting can be provided to configure RTA/RTP process system700to provide adjusted radiation to a different substrate that has yet to undergo the epitaxy process operation. The adjusted radiation can be provided by radiation elements108to process chamber110. The post-implantation anneal process operation can be performed in process chamber110. Based on the radiation energy data and the measurement data, computing device102or RTA/RTP process system700can adjust the number of radiation elements108to be turned on, the level of heat (e.g., low, medium, and high) to be provided by radiation elements108, the resistance of radiation elements108, and whether to employ cooling module112. The adjusted radiation setting can assist in optimizing the radiation conditions in process chamber110and in achieving the doped layer dopant concentration within a predetermined range. If the radiation conditions are not optimized or if the doped layer dopant concentration remains outside the predetermined range, further adjustments can be made to the radiation settings. Because the radiation energy data and the measurement data can be monitored and fed into the radiation settings constantly or periodically, radiation conditions in process chamber110can be controlled to yield the doped layer dopant concentration within the predetermined range. The radiation energy data can also facilitate replacing aged radiation elements108. Radiation control method400and radiation control system100can improve yield and quality for the post-implantation anneal process operation. The radiation energy data feedback can be substantially in real time. The doped layer dopant concentration data feedback can be substantially in real time because EIS can measure the dopant concentration data in-situ. In some embodiments, the doped layer dopant concentration data feedback can be after the substrate completes the post-implantation anneal process operation.

FIG.8is an illustration of an example computing device102ofFIG.1in which various embodiments of the present disclosure can be implemented, according to some embodiments. Computing device102can be a computer capable of performing the functions and operations described herein, such as the operations of method400inFIG.4. For example, and without limitation, computing device102can be capable of receiving, processing, and transmitting signals and commands. Computing device102can be used, for example, to receive radiation energy data and measurement data, analyze the radiation energy data and the measurement data, and adjust radiation settings based on the radiation energy data and the measurement data. Computing device102can be used, for example, to send radiation settings to radiation device114and configure radiation device114ofFIG.1to provide radiation to process chamber110based on the radiation settings. Computing device102can be used, for example, to send radiation settings to adjustment device106and configure adjustment device106ofFIG.1to adjust radiation elements108based on the radiation settings.

Computing device102includes one or more processors (also called central processing units, or CPUs), such as a processor804. Processor804is connected to a communication infrastructure or bus806. Computing device102also includes input/output device(s)803, such as touch screens, monitors, keyboards, pointing devices, etc., that communicate with communication infrastructure or bus806through input/output interface(s)802. Computing device102can receive instructions to implement functions and operations described herein—e.g., receiving the radiation energy data and the measurement data, analyzing the radiation energy data and the measurement data, adjusting the radiation settings, sending the radiation energy data and the measurement setting, configuring radiation device114and adjustment device106, and method400—via input/output device(s)803. Computing device102can also include a main or primary memory808, such as random access memory (RAM). Main memory808can include one or more levels of cache. Main memory808has stored therein control logic (e.g., computer software) and/or data. In some embodiments, the control logic (e.g., computer software) and/or data can include one or more of the functions described above with respect to receiving the radiation energy data and the measurement data, analyzing the radiation energy data and the measurement data, adjusting the radiation settings, sending the radiation energy data and the measurement setting, configuring radiation device114and adjustment device106, and method400.

Computing device102can also include one or more secondary storage devices or secondary memory810. Secondary memory810can include, but is not limited to, a hard disk drive812and/or a removable storage device or drive814. Removable storage drive814can be a floppy disk drive, a magnetic tape drive, a compact disk drive, an optical storage device, tape backup device, and/or any other storage device/drive.

Removable storage drive814can interact with a removable storage unit818. Removable storage unit818includes a computer usable or readable storage device having stored thereon computer software (control logic) and/or data. Removable storage unit818can be a floppy disk, magnetic tape, compact disk, DVD, optical storage disk, and/or any other computer data storage device. Removable storage drive814reads from and/or writes to removable storage unit818in a well-known manner.

According to some embodiments, secondary memory810can include other means, instrumentalities or other approaches for allowing computer programs and/or other instructions and/or data to be accessed by computing device102. Such means, instrumentalities or other approaches can include, but is not limited, a removable storage unit822and an interface820. Examples of the removable storage unit822and the interface820can include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an EPROM or PROM) and associated socket, a memory stick and USB port, a memory card and associated memory card slot, and/or any other removable storage unit and associated interface. In some embodiments, secondary memory810, removable storage unit818, and/or removable storage unit822can include one or more of the functions described above with respect to the holder.

Computing device102can further include a communication or network interface824. Communication interface824enables computing device102to communicate and interact with any combination of remote devices, remote networks, remote entities, etc. (individually and collectively referenced by reference number828). For example, communication interface824can allow computing device102to communicate with element828(e.g., remote devices) over communications path826, which can be wired and/or wireless, and which can include any combination of LANs, WANs, the Internet, etc. Control logic and/or data can be transmitted to and from computing device102via communication path826.

The functions/operations in the preceding embodiments can be implemented in a wide variety of configurations and architectures. Therefore, some or all of the operations in the preceding embodiments—e.g., receiving the radiation energy data and the measurement data, analyzing the radiation energy data and the measurement data, adjusting the radiation settings, sending the radiation energy data and the measurement setting, configuring radiation device114and adjustment device106, and method400—can be performed in hardware, in software or both. In some embodiments, a tangible system or article of manufacture including a tangible computer useable or readable medium having control logic (software) stored thereon is also referred to herein as a computer program product or program storage device. This includes, but is not limited to, computing device102, main memory808, secondary memory810and removable storage units818and822, as well as tangible articles of manufacture embodying any combination of the foregoing. Such control logic, when executed by one or more data processing devices (such as computing device102), causes such data processing devices to operate as described herein. In some embodiments, computing device102includes hardware/equipment for the manufacturing of photomasks and circuit fabrication. For example, the hardware/equipment can be connected to or be part of element828(remote device(s), network(s), entity(ies)828) of computing device102.

The present disclosure is directed to a method (e.g., method400) for providing radiation control in radiation devices (e.g., radiation device114) based on radiation energy data and substrate measurement data feedback and an example system (e.g., system100) for performing the method. A computing device (e.g., computing device102) can provide an initial radiation setting to a radiation device. The initial radiation setting can be based on temperature data collected on a test substrate equipped with one or more thermal sensors. The initial radiation setting can be additionally and/or alternatively based on measurement data collected on a test substrate that has completed a process operation of interest. The radiation device can provide radiation to a substrate, such as a production wafer, based on the initial radiation setting. Detection devices (e.g., detection device104) can be placed at different locations in the radiation device and collect radiation energy data. One exemplary detection device can include an optical fiber and a photodetector. The computing device can analyze the radiation energy data. If a variance of the radiation energy data is above a predetermined threshold, indicating the radiation energy distribution or non-uniformity is unacceptable, the computing device can adjust the radiation setting and provide the adjusted radiation setting to the radiation device. The radiation device can provide adjusted radiation based on the adjusted radiation setting to the substrate in substantially real time. The radiation device can also provide adjusted radiation based on the adjusted radiation setting to a subsequent substrate, where the subsequent substrate has yet to undergo the process operation. The radiation device can adjust radiation in different ways. For example, an adjustment device (e.g., adjustment device106) can be used to adjust a tilt angle of a radiation element. One exemplary adjustment device can include a motor, such as a stepper motor, a spring, and a lever. In some embodiments, the radiation device can adjust a resistance of a radiation element. In some embodiments, the radiation device can generate an instruction to replace an aged radiation element.

Additionally and/or alternatively, substrate measurement data feedback can be used to control radiation conditions. After the substrate completes the process operation, a measuring device (e.g., measuring device116) can collect data, such as critical dimension (CD) data, on the substrate. The measurement data can include optical metrology data, optical inspection data, profilometer data, spectrometry data, EIS data, SEM data, TEM data, and a combination thereof. In some embodiments, the measurement data can be thickness data of an epitaxial layer on the substrate. In some embodiments, the measurement data can be thickness data of an oxide layer on the substrate. In some embodiments, the measurement data can be dopant concentration data of a doped layer on the substrate. In some embodiments, the measurement data can be contamination percentage data of the substrate. The computing device can analyze the measurement data. If a difference between reference data and the measurement data on the substrate is above another predetermined threshold, also indicating the radiation energy distribution or non-uniformity is unacceptable, the computing device can further adjust the radiation setting and provide the adjusted radiation setting to the radiation device. The radiation device can then provide adjusted radiation based on the further adjusted radiation setting to a subsequent substrate. In some embodiments, the measurement device can collect in-situ data on the substrate, and the radiation device can provide adjusted radiation based on the further adjusted radiation setting to the substrate in substantially real time. In some embodiments, the radiation device can analyze the radiation energy data and the measurement data and adjust the radiation setting itself. The method and example system in the present disclosure can improve radiation distribution and uniformity in substantially real time. The improved radiation uniformity can reduce fabrication complexity, reduce defects, improve yield, and improve device reliability.

In some embodiments, a method includes sending a first setting to configure a radiation device to provide radiation to a substrate undergoing a process operation in a process chamber of the radiation device. The method further includes receiving radiation energy data measured at a plurality of locations of the process chamber and receiving measurement data measured on the substrate during the process operation. The method further includes in response to a variance of the radiation energy data being above a first predetermined threshold and in response to a difference between reference data and the measurement data being above a second predetermined threshold, sending a second setting to configure the radiation device to provide radiation to the substrate.

In some embodiments, a method includes receiving, by a radiation device, a radiation setting including a tilt angle of a radiation element of the radiation device and providing radiation, based on the radiation setting, to a first substrate undergoing a process operation in a process chamber of the radiation device. The method further includes in response to a variance of radiation energy data being above a predetermined threshold, receiving an adjustment in the tilt angle of the radiation element, where the radiation energy data is measured at a plurality of locations of the process chamber. The method further includes providing radiation, based on the adjusted radiation setting, to a second substrate that has yet to undergo the process operation.

In some embodiments, a system includes a computing device configured to generate first and second radiation settings. The system further includes a radiation device including one or more radiation elements and a process chamber, the radiation device configured to receive the first and second radiation settings and provide radiation, based on the first and second radiation settings, to a substrate undergoing a process operation in the process chamber. The system further includes a detection device configured to measure radiation energy data at a plurality of locations of the process chamber, where the second radiation setting is based on a variance of the radiation energy data being above a predetermined threshold. The system further includes an adjustment device including a spring, a lever, and a stepper motor, the adjustment device configured to adjust a tilt angle of the one or more radiation elements based on the second radiation setting.