Patent ID: 12189311

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

Further, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly.

A reticle (or another type of lithography mask) may be secured to a reticle stage of an exposure tool by an electrostatic clamp. After an exposure operation, the reticle may be removed from the reticle stage and placed in a reticle carrier. The reticle may be transported in the reticle carrier, which may be sealed to reduce and/or minimize ingress of humidity, oxygen, and/or particles (e.g., dust, debris, and/or other foreign objects) from damaging the reticle.

A reticle that is placed in a reticle carrier may have a residual charge that remains on the reticle after discharge of the electrostatic clamp. The residual charge may attract particles in the reticle carrier onto the reticle because of the difference in charge between the lithography mask and the mask stage. The particles may affect the pattern that is transferred from the reticle to a substrate. This can have significant impacts on semiconductor device manufacturing quality and yield, as any pattern defects may be repeatedly transferred to hundreds or thousands of substrates, which can lead to waste and additional semiconductor device manufacturing to replace the defective semiconductor devices.

Some implementations described herein provide reticle carriers, methods of use, and methods of formation. In some implementations, a reticle carrier described herein is configured to quickly discharge the residual charge on a reticle so as to reduce, minimize, and/or prevent particles in the reticle carrier from being attracted to and/or transferred to the reticle. In particular, the reticle carrier may be configured to provide reduced capacitance between an inner baseplate of the reticle carrier and the reticle. The reduction in capacitance may reduce the resistance-capacitance (RC) time constant for discharging the residual charge on the reticle, which may increase the discharge speed for discharging the residual charge through support pins of the reticle carrier. The increase in discharge speed may reduce the likelihood that an electrostatic force in the reticle carrier may attract particles in the reticle carrier to the reticle. This may reduce pattern defects transferred to substrates that are patterned using the reticle, may increase semiconductor device manufacturing quality and yield, and may reduce scrap and rework of semiconductor devices and/or wafers.

FIG.1is a diagram of an example semiconductor processing environment100described herein. The semiconductor processing environment100may include an environment in which substrates, such as semiconductor wafers, semiconductor devices, reticles, photomasks, and/or other components in a semiconductor fabrication facility, are processed through exposure operations to form pattern on the substrates for further processing in the semiconductor fabrication facility.

As shown inFIG.1, the semiconductor processing environment100may include an exposure tool102, a load port104on which a reticle carrier106may be positioned and/or supported, an interface tool108, and a load lock chamber110connecting the exposure tool102and the interface tool108.

The interface tool108may be configured to transfer reticles between the load port104and the exposure tool102. The interface tool108may include an equipment front end module (EFEM) or similar type of interface tool that is situated between the load port104and the exposure tool102. The interface tool108may include a chamber112that is sealed from the external environment of the semiconductor processing environment100to reduce and/or minimize contamination of reticles that are transferred through the interface tool108.

The interface tool108may further include a reticle transport device114in the chamber112. The reticle transport device114may include a robotic arm or another type of tool that is configured to transport reticles between the reticle carrier106and the exposure tool102through the load lock chamber110. The load lock chamber110may include a chamber that is configured to permit the transfer of reticles between the interface tool108and the exposure tool102while maintaining environmental isolation between the interface tool108and the exposure tool102.

The exposure tool102is a semiconductor processing tool that is capable of exposing a photoresist layer on a substrate to a radiation source, such as an ultraviolet light (UV) source (e.g., a deep UV light source, an extreme UV (EUV) light source, and/or the like), an x-ray source, an electron beam source, and/or another type of radiation source. The exposure tool102may expose a photoresist layer to the radiation source to transfer a pattern from a reticle (or a photomask) to the photoresist layer. The pattern may include one or more semiconductor device layer patterns for forming one or more semiconductor devices on the substrate, may include a pattern for forming one or more structures of a semiconductor device on the substrate, and/or may include a pattern for etching various portions of a semiconductor device and/or the substrate, among other examples. In some implementations, the exposure tool102includes a scanner, a stepper, an immersion lithography tool, an EUV lithography tool, or a similar type of exposure tool.

The exposure tool102may include a chamber116and a reticle transport device118in the chamber116. A vacuum (or an ultra-high vacuum) may be maintained in the chamber116so that EUV exposure operations may be performed. The reticle transport device118may include a robotic arm or another type of tool that is configured to transport reticles between the exposure tool102and the load lock chamber110. The exposure tool102may further include a cover rack120that is configured to support and/or secure an internal cover of the reticle carrier106while a reticle associated with the reticle carrier106is in use in the exposure tool102. The reticle transport device118may position an internal cover of the reticle carrier106on one or more support members of the cover rack120to access the reticle associated with the reticle carrier106.

The exposure tool102may include an exchanging station122configured to support and/or secure an inner baseplate of the reticle carrier106and the reticle associated with the reticle carrier106. The exchanging station122may be further configured to move to various locations within the chamber116to position the reticle for securing to a reticle stage124of the exposure tool102, to position the inner baseplate for retrieval of the reticle from the reticle stage124, and/or to position the reticle and the inner baseplate for retrieval by the reticle transport device118.

The reticle stage124may include an electrostatic chuck that is configured to secure the reticle in place for an exposure operation by an electrostatic clamp. The reticle stage124may form the electrostatic clamp by generating an electric potential (or an electrostatic field) between the reticle stage124and the reticle. The electric potential secures the reticle to the reticle stage124. The reticle stage124may release the electrostatic clamp so that the reticle may be returned to the reticle carrier106, and so that another reticle may be placed on the reticle stage124for another exposure operation.

In some implementations, the exposure tool102includes additional components to those shown inFIG.1. For example, the exposure tool102may include an immersion lithography tool that operates in a deep UV spectrum, and may include a system of transmissive lenses that is configured to collimate, focus, collect, filter and/or direct UV radiation from a radiation source through a reticle or photomask and toward a substrate. As another example, the exposure tool102may include an EUV lithography tool that operates in an EUV spectrum, and may include a system of reflective mirrors that is configured to collimate, focus, collect, filter and/or direct UV radiation from a radiation source off of a reticle or photomask and toward a substrate.

As indicated above,FIG.1is provided as an example. Other examples may differ from what is described with regard toFIG.1.

FIGS.2A and2Bare diagrams of an example reticle carrier106described herein for use in the example semiconductor processing environment100ofFIG.1. In some cases, a residual charge may remain on a reticle from the electrostatic clamp that is used to secure the reticle to the reticle stage124(e.g., after the electrostatic clamp is released). Accordingly, the reticle carrier106may be configured to quickly discharge the residual charge on a reticle that is positioned in the reticle carrier106so as to reduce, minimize, and/or prevent particles in the reticle carrier from being attracted to and/or transferred to the reticle.

As shown inFIG.2A, the reticle carrier106may include a housing202that includes an upper shell204and a lower shell206.FIG.2Aillustrates an assembled configuration of the housing202, in which the upper shell204is mated or coupled with the lower shell206. An overhead hoist transport (OHT) head208may be included on a top portion of the upper shell204to permit the reticle carrier106to be transported by an OHT vehicle, by an automated material handling system (AMHS), by a reticle stocker, and/or by another automated transport device. As an example, a lift of an OHT vehicle may latch onto the OHT head208to load the reticle carrier106into the OHT vehicle and to secure the reticle carrier106while the reticle carrier106is transported in the OHT vehicle. Moreover, the lift of the OHT vehicle may unlatch from the OHT head208to provide the reticle carrier106to a location such as a staging area of a reticle storage system or to a load port (e.g., the load port104) associated with an exposure tool (e.g., the exposure tool102).

In some implementations, one or more dimensions of the housing202, the upper shell204, the lower shell206, and/or the OHT head208may be configured to conform to and/or satisfy one or more standardized reticle carrier dimensional parameters to permit the reticle carrier106to be transported by various types of reticle transport devices. The one or more standardized reticle carrier dimensional parameters may include one or more parameters of a reticle carrier specification, such as SEMI E100, SEMI E111, and/or SEMI E112. The one or more dimensions may include external dimensions of the reticle carrier106, such as a length dimension (the x dimension inFIG.2A) of the housing202, a width dimension (the y dimension inFIG.2A) of the housing202, and/or a height dimension (the z dimension inFIG.2A) of the housing202. The external dimensions may be based a particular size of reticle (or a range of sizes of reticles) that the reticle carrier106is to transport, such as 6 inch reticles, 150 millimeter reticles, or 230 millimeter reticles, among other examples. An example range for the length dimension (the x dimension inFIG.2A) may include approximately 175 millimeters to approximately 300 millimeters. An example range for the width dimension (the y dimension inFIG.2A) may include approximately 150 millimeters to approximately 230 millimeters. An example range for the height dimension (the z dimension inFIG.2A) may include approximately 26 millimeters to approximately 100 millimeters. However, other values or ranges for the x dimension, the y dimension, and/or the z dimension are within the scope of the present disclosure.

FIG.2Billustrates an exploded configuration of housing202in which the upper shell204and the lower shell206are separated to expose an inner space210of the reticle carrier106. The upper shell204and the lower shell206may be configured to form and enclose the inner space210when the upper shell204and the lower shell206are coupled. As further shown inFIG.2B, the reticle carrier106may include an inner cover212and an inner baseplate214. The inner cover212and the inner baseplate214may be sized and/or otherwise configured to fit within the inner space210formed by the upper shell204and the lower shell206. Moreover, the inner cover212and the inner baseplate214may be sized and/or otherwise configured to secure or hold a reticle216, and to permit secure transport of the reticle216in the reticle carrier106. The reticle216may include an EUV reticle, an immersion lithography photomask, or another type of device on which a lithography pattern is included. The lithography pattern may be transferred to a substrate through reflection of radiation off of the lithography pattern or by transmission of the radiation through the lithography pattern.

The upper shell204, the lower shell206, the OHT head208, the inner cover212, and/or the inner baseplate214may be formed of various types of materials, including non-conductive materials and/or conductive materials. In some implementations, the upper shell204, the lower shell206, the OHT head208, the inner cover212, and/or the inner baseplate214are formed of a plastic or a polymer material. In some implementations, one or more portions of the upper shell204, the lower shell206, the OHT head208, the inner cover212, and/or the inner baseplate214are formed of a conductive material that is electrically connected to an electrical grounding point to permit a residual charge on the reticle216to be discharged through one or more portions of the reticle carrier106.

As indicated above,FIGS.2A and2Bare provided an example. Other examples may differ from what is described with regard toFIGS.2A and2B.

FIG.3is a diagram of an example implementation300of the reticle carrier106ofFIGS.2A and2Bdescribed herein. The example implementation300may include an example in which the reticle carrier106includes support pins, on which the reticle216is to be secured, are configured such that the distance between the inner baseplate214and the reticle216reduces the capacitance between an inner baseplate214and the reticle216. The reduction in capacitance may reduce the RC time constant for discharging a residual charge on the reticle216, which may increase the discharge speed for discharging the residual charge through the support pins of the reticle carrier106. The increase in discharge speed may reduce the likelihood that an electrostatic force in the reticle carrier106attract particles in the reticle carrier106to the reticle216and/or may reduce the size of particles that are attracted to the reticle216.

As shown inFIG.3, the reticle216may be positioned within an inner space302formed by the inner cover212and the inner baseplate214. The reticle carrier106may include a plurality of support pins304that are configured to maintain the reticle216off of the inner baseplate214in the inner space302. The reticle carrier106may include additional support members306in and/or on the inner cover212to secure the reticle216in place and to prevent vibration and/or other types of movement of the reticle carrier106from causing the reticle216to contact the inner cover212. The inner cover212may include a filter308that is configured to filter the air or gas, that is provided to the inner space302, of particles and/or other types of contaminants. The inner baseplate214may include a plurality of alignment windows310that permit the reticle216to be properly aligned when securing the reticle to the reticle stage124.

As shown in a close-up view312inFIG.3, the reticle216may have a negative residual charge when placed in the reticle carrier106. The inner baseplate214may be maintained at a positive charge. The difference in polarity between the reticle216and the inner baseplate214may cause an electric field to be generated between the reticle216and the inner baseplate214. The electric field may apply a force to particles314on the inner baseplate214. The force may attract the particles314toward and onto the reticle216. The stronger the electric field is, the stronger the force that is applied to the particles314. Accordingly, the stronger the electric field, the larger the size of particles314that may be attracted to the reticle216.

To reduce the effect of the electric field, the inner baseplate214may be connected to an electrical ground such that the residual charge on the reticle216may be discharged through the support pins304. However, a capacitive effect between the negatively charged reticle216and the positively charged inner baseplate214may slow or reduce the speed of discharge of the residual charge from the reticle216. The capacitive effect promotes the storage of charge between the reticle216and the inner baseplate214, which resists the discharge of the residual charge from the reticle216. This increases the RC time constant for discharging the residual charge, which increases the time duration to fully discharge the residual charge.

Accordingly, the support pins304may be configured to facilitate discharging of a residual charge on the reticle216when the reticle216is placed in the reticle carrier106. In particular, the support pins304may be sized such that a distance (d1) between the reticle216and the inner baseplate214(e.g., the surface of the inner baseplate214facing or orientated toward the reticle216) reduces and/or minimizes the capacitance between the reticle216and the inner baseplate214. In this way, the distance (d1) may be configured to reduce, minimize, and/or prevent the attraction of particles314toward the reticle216that might otherwise be caused by the residual charge on the reticle216.

In the example implementation300, the distance (d1) may correspond to the height (h1) of the support pins304from the inner baseplate214to the top316of the support pins304. Thus, the greater the height (h1) of the support pins304(and thus, the greater the distance (d1)) the lower the capacitance between the reticle216and the inner baseplate214for the same area reticle216, the same area inner baseplate214, and the same permittivity between the reticle216and the inner baseplate214. The lower the capacitance between the reticle216and the inner baseplate214, the quicker the discharge speed of the residual charge on the reticle216through a discharge path318through the support pins304. The quicker the discharge speed, the smaller the size (e.g., the smaller the radius (r1)) of particles314that are likely to be attracted toward the reticle216. As an example, the height (h1) of the support pins304may be configured as approximately 200 microns to prevent particles314having a radius (r1) equal to or greater than approximately 147 nanometers from being attracted to the reticle216. As another example, the height (h1) of the support pins304may be configured as approximately 400 microns to prevent particles314having a radius (r1) equal to or greater than approximately 75 nanometers from being attracted to the reticle216. As another example, the height (h1) of the support pins304may be configured as approximately 1000 microns to prevent particles314having a radius (r1) equal to or greater than approximately 22 nanometers from being attracted to the reticle216. In some implementations, the height (h1) of the support pins304(and thus, the greater the distance (d1)) may be in a range of approximately 1150 microns to approximately 4000 microns to provide a sufficient capacitance decrease while minimizing the increase to the overall weight of the reticle carrier106and impact to reticle transport devices114and118. However, other values for the distance (d1) and the height (h1) are within the scope of the present disclosure.

In some implementations, the height (h1) of the support pins304(and thus, the greater the distance (d1)) may be determined and configured based on a model. The model may be used to determine or estimate the distance (d1) between the inner baseplate214and the reticle216(and thus, the height (h1) of the support pins304) such that one or more parameter thresholds are satisfied. The one or more threshold parameters may include, for example, a threshold particle size, a capacitance threshold, an electrostatic force threshold, and/or another threshold parameter threshold.

In some implementations, a device (e.g., the device600described herein in connection withFIG.6) may determine the threshold particle size to prevent particles314equal to or greater than the threshold particle size from being electrostatically attracted to the reticle216. The device may use the model to determine the distance (d1) between the inner baseplate214and the reticle216(and thus, the height (h1) of the support pins304) such that capacitance threshold for a capacitance between the inner baseplate214and the reticle216is satisfied. In this way, the device may determine the capacitance, using the model, such that the capacitance is low enough to quickly discharge the residual charge on the reticle216so as to prevent particles314equal to or greater than the threshold particle size from being electrostatically attracted to the reticle216.

The model may include an electrostatic force threshold for attracting particles314equal to and/or greater than the threshold particle size to the reticle216. The device may determine the electrostatic force threshold based on:
FE=QinducedE(t)
where Qinducedcorresponds to the magnitude of the residual charge on the reticle216and E(t) is the electric field magnitude of an estimated electric field (which may be time-varying during discharging of the residual charge) between the inner baseplate214and the reticle216. The device may determine the electric field magnitude based on:

E⁡(t)=V⁡(t)d
where V(t) corresponds to an electric potential (which may be time-varying during discharging of the residual charge) between the inner baseplate214and the reticle216and d corresponds to the distance (d1) and the height (h1). The device may determine the electric potential based on:

V⁡(t)=Q⁡(t)C
where Q(t) corresponds to the time-varying residual charge (which may be referred to as a discharge rate parameter) on the reticle216and C corresponds to the capacitance between the inner baseplate214and the reticle216. The device may determine the time-varying residual charge based on:

Q⁡(t)=Q0⁢-teRSupport⁢C
where Q0corresponds to the initial magnitude of the residual charge prior to discharging, RSupportcorresponds to the resistance of the support pins304, and C corresponds to the capacitance between the inner baseplate214and the reticle216. The resistance of the support pins304(RSupport) and the distance (d1) and the height (h1) correspond to the RC time constant between the inner baseplate214and the reticle216.

Based on the relationships defined above, the device may determine the exponential decay of the residual charge based on the resistance of the support pins304(RSupport) and the distance (d1) and the height (h1) to satisfy a particular discharge rate parameter associated with the reticle216. In particular, the device may determine the distance (d1) and the height (h1) to increase or decrease the RC time constant, and thus the rate of exponential decay of the residual charge, to correspondingly increase or decrease the time-varying electric potential and the time-varying electric field magnitude to satisfy the electrostatic force threshold. Accordingly, the greater the distance (d1) and the height (h1) determined by the device, the lesser the electrostatic force that is to be applied to particles314in the reticle carrier106, which reduces the size of particles314that are attracted to the reticle216.

As indicated above,FIG.3is provided an example. Other examples may differ from what is described with regard toFIG.3.

FIGS.4A and4Bare diagrams of an example implementation400of the reticle carrier106ofFIGS.2A and2Bdescribed herein. The example implementation400may include an example in which the reticle carrier106includes a recessed region in a portion of the inner baseplate214. The recessed region results in the distance between the reticle216and the inner baseplate214being greater in the portion of the inner baseplate214that includes the recessed region. The increased distance provided by the recessed region reduces the capacitance between an inner baseplate214and the reticle216. The reduction in capacitance may reduce the RC time constant for discharging a residual charge on the reticle216, which may increase the discharge speed for discharging the residual charge through the support pins of the reticle carrier106. The increase in discharge speed may reduce the likelihood that an electrostatic force in the reticle carrier106attract particles314in the reticle carrier106to the reticle216and/or may reduce the size of particles314that are attracted to the reticle216.

As shown in the cross-sectional view inFIG.4A, the reticle carrier106may include elements402-410in the example implementation400, which may be similar to elements302-310in the example implementation300. However, the inner baseplate214of the reticle carrier106may include a recessed region412. The recessed region412may be located in a portion of the inner baseplate214over which the reticle216is configured to be positioned. The distance between the inner baseplate214in the recessed region412and the reticle216may be greater relative to a distance between the inner baseplate214in a non-recessed portion414and the reticle216to decrease the capacitance between the inner baseplate214and the reticle216(and thus, to increase the discharge rate of the residual charge on the reticle216).

As shown in a close-up portion416inFIG.4A, the recessed region412may be included in the inner baseplate214and may have a depth (d2) relative to a top surface of the non-recessed portion414. The depth (d2) of the recessed region may be in a range of approximately 1000 microns to approximately 3500 microns to provide a sufficient discharge rate of the residual charge on the reticle216and to minimize the increase to the overall weight of the reticle carrier106and impact to reticle transport devices114and118. However, other values for the depth (d2) are within the scope of the present disclosure. The thickness (t1) of the inner baseplate214in the recessed region412may be in a range of approximately 5000 microns to approximately 7500 microns to provide sufficient strength and structural rigidity for the inner baseplate214. However, other values for the thickness (t1) are within the scope of the present disclosure. The ratio between the depth (d2) and the thickness (t1) of the baseplate in the recessed region may be in a range of approximately 0.13 to approximately 0.7 to provide a sufficiently deep recessed region412and to maintain sufficient structural rigidity for the inner baseplate214. However, other values for the ratio are within the scope of the present disclosure.

As indicated above in connection withFIG.3, a device (e.g., the device600described in connection withFIG.6) may use the model to determine the distance between the inner baseplate214and the reticle216to satisfy one or more parameter thresholds. Similarly, the device may use the model described above to determine the depth (d2) of the recessed region412and/or a height (h2) of the support pins404(which may correspond to a distance (d3) between the inner baseplate214in the non-recessed portion414and a top418of the support pins404) such that an overall distance (d4) between the inner baseplate214and the reticle216in the recessed region412satisfies one or more parameter thresholds. As an example, the device may determine to increase the height (h2) of the support pins404and/or increase the depth (d2) of the recessed region412to increase the overall distance (d4), which may increase the discharge rate of discharging the residual charge on the reticle216. In some implementations, the overall distance (d4) is in a range of approximately 1150 microns to approximately 4000 microns to provide a sufficient capacitance decrease while minimizing the increase to the overall weight of the reticle carrier106and the impact to reticle transport devices114and118. However, other values for the overall distance (d4) are within the scope of the present disclosure. In this way, the device may use the model to satisfy a capacitance threshold for a capacitance between the inner baseplate214and the reticle216based on a threshold particle size to satisfy a discharge rate parameter associated with the reticle216, and/or to satisfy another parameter or parameter threshold.

As shown in a top-down view inFIG.4B, the recessed region412may be included within a perimeter420defined by support pins404a,404b,404c, and404d. Moreover, the recessed region412may extend between two support pins, such as between support pins404aand404b, between support pins404aand404c, between support pins404band404d, and between support pins404cand404d. A width (w1) of the recessed region412, that is in between two support pins (e.g., the support pins404aand404b) may be in a range of approximately 130 millimeters to approximately 140 millimeters so that the recessed region412fits in between the support pins and provides sufficiently low capacitance between the inner baseplate214and the reticle216. However, other values for the width (w1) are within the scope of the present disclosure. A width (w2) of the recessed region412, that is not in between two support pins (e.g., the support pins404aand404b) may be in a range of 140 millimeters to approximately 155 millimeters so that the recessed region412fully extends to the outside edges of the support pins and provides sufficiently low capacitance between the inner baseplate214and the reticle216. However, other values for the width (w2) are within the scope of the present disclosure.

As indicated above,FIGS.4A and4Bare provided an example. Other examples may differ from what is described with regard toFIGS.4A and4B.

FIGS.5A-5Kare diagrams of an example implementation500described herein. The example implementation500may include an example of transferring the reticle216from the reticle stage124to the reticle carrier106.

As shown inFIG.5A, the reticle216may be secured to the reticle stage124, which may include an electrostatic chuck. The reticle216may be secured to the reticle stage124by an electrostatic clamp, where opposing charges on the reticle216and on the reticle stage124attract the reticle216toward the reticle stage124. The exposure tool102may perform an exposure operation in which the reticle216is used to transfer a pattern of the reticle216to a substrate as part of formation of one or more semiconductor devices on the substrate. As further shown inFIG.5A, the inner baseplate214of the reticle carrier106may be positioned on the exchanging station122in preparation for receiving the reticle216. The inner cover212may be positioned in one of the slots of the cover rack120.

As shown inFIG.5B, the exposure tool102may move the exchanging station122to position the inner baseplate214under the reticle216. For example, the exposure tool102may move the exchanging station122to position the inner baseplate214under the reticle216after the exposure operation to exchange out the reticle216(e.g., for another reticle). With the inner baseplate214positioned under the reticle216, the exposure tool102may release the electrostatic clamp between the reticle stage124and the reticle216. This causes the reticle216to be no longer secured to the reticle stage124and, instead, supported on the inner baseplate214. In particular, the reticle216may be supported on the plurality of support pins (e.g., the support pins304and/or404) included on the inner baseplate214.

As described above, a residual charge may remain on the reticle216after release of the electrostatic clamp. Accordingly, the residual charge may begin to be discharged through the plurality of support pins when the reticle216is positioned on the plurality of support pins. The distance (d1, d4) between the reticle216and the inner baseplate214may be configured, as described above in connection withFIG.3orFIGS.4A and4B, to reduce, minimize, and/or prevent the attraction of particles314of a particular size from the inner baseplate214of the reticle carrier106to the reticle216. As an example, the distance (d1, d4) between the reticle216and the inner baseplate214may be configured, as described above in connection withFIG.3orFIGS.4A and4B, to reduce, minimize, and/or prevent the attraction of particles314equal to or greater than a threshold particle size.

As shown inFIG.5C, the exposure tool102may lower or otherwise move the exchanging station122toward the cover rack120. As shown inFIG.5D, the reticle transport device118may move toward the exchanging station122and may retrieve the reticle216on the inner baseplate214from the exchanging station122.

As shown inFIG.5E, the reticle transport device118may position the inner baseplate214, with the reticle216positioned on the inner baseplate214, under the inner cover212in the cover rack120. In some implementations, the reticle transport device118moves the reticle216and the inner baseplate214upward so that the inner cover212is positioned over and on the inner baseplate214such that the reticle216is enclosed in an inner space (e.g., the inner space302and/or402) formed between the inner cover212and the inner baseplate214. In some implementations, the inner cover212is lowered onto the inner baseplate214such that the reticle216is enclosed in the inner space formed between the inner cover212and the inner baseplate214.

As shown inFIG.5F, the reticle transport device118may position the inner cover212and the inner baseplate214(with the reticle216enclosed therein) in front of the load lock chamber110. As shown inFIG.5G, the reticle transport device118may extend such that the inner cover212and the inner baseplate214(with the reticle216enclosed therein) are positioned in the load lock chamber110in preparation for passing the inner cover212and the inner baseplate214(with the reticle216enclosed therein) to the reticle transport device114.

As shown inFIG.5H, the reticle transport device114may retrieve the inner cover212and the inner baseplate214(with the reticle216enclosed therein) from the reticle transport device118. As shown inFIG.5I, the reticle transport device114may retract the inner cover212and the inner baseplate214(with the reticle216enclosed therein) from the load lock chamber110and into the chamber112of the interface tool108.

As shown inFIG.5J, the reticle transport device114may extend the inner cover212and the inner baseplate214(with the reticle216enclosed therein) out of the chamber112and onto the lower shell206of the reticle carrier106. The lower shell206may be positioned on the load port104in preparation for receiving the inner cover212and the inner baseplate214(with the reticle216enclosed therein). As shown inFIG.5K, the upper shell204may be placed onto the lower shell206such that the inner cover212and the inner baseplate214(with the reticle216enclosed therein) are positioned in the inner space210formed by the upper shell204and the lower shell206. Accordingly, an OHT vehicle or another type of transport device may retrieve the reticle carrier106from the load port104and may transport the reticle carrier106to another location such as a reticle storage system.

As indicated above,FIGS.5A-5Kare provided an example. Other examples may differ from what is described with regard toFIGS.5A-5K.

FIG.6is a diagram of example components of a device600. In some implementations, the exposure tool102, the load port104, the interface tool108, the reticle transport device114, and/or the reticle transport device118may include one or more devices600and/or one or more components of device600. As shown inFIG.6, device600may include a bus610, a processor620, a memory630, a storage component640, an input component650, an output component660, and a communication component670.

Bus610includes a component that enables wired and/or wireless communication among the components of device600. Processor620includes a central processing unit, a graphics processing unit, a microprocessor, a controller, a microcontroller, a digital signal processor, a field-programmable gate array, an application-specific integrated circuit, and/or another type of processing component. Processor620is implemented in hardware, firmware, or a combination of hardware and software. In some implementations, processor620includes one or more processors capable of being programmed to perform a function. Memory630includes a random access memory, a read only memory, and/or another type of memory (e.g., a flash memory, a magnetic memory, and/or an optical memory).

Storage component640stores information and/or software related to the operation of device600. For example, storage component640may include a hard disk drive, a magnetic disk drive, an optical disk drive, a solid state disk drive, a compact disc, a digital versatile disc, and/or another type of non-transitory computer-readable medium. Input component650enables device600to receive input, such as user input and/or sensed inputs. For example, input component650may include a touch screen, a keyboard, a keypad, a mouse, a button, a microphone, a switch, a sensor, a global positioning system component, an accelerometer, a gyroscope, and/or an actuator. Output component660enables device600to provide output, such as via a display, a speaker, and/or one or more light-emitting diodes. Communication component670enables device600to communicate with other devices, such as via a wired connection and/or a wireless connection. For example, communication component670may include a receiver, a transmitter, a transceiver, a modem, a network interface card, and/or an antenna.

Device600may perform one or more processes described herein. For example, a non-transitory computer-readable medium (e.g., memory630and/or storage component640) may store a set of instructions (e.g., one or more instructions, code, software code, and/or program code) for execution by processor620. Processor620may execute the set of instructions to perform one or more processes described herein. In some implementations, execution of the set of instructions, by one or more processors620, causes the one or more processors620and/or the device600to perform one or more processes described herein. In some implementations, hardwired circuitry may be used instead of or in combination with the instructions to perform one or more processes described herein. Thus, implementations described herein are not limited to any specific combination of hardware circuitry and software.

The number and arrangement of components shown inFIG.6are provided as an example. Device600may include additional components, fewer components, different components, or differently arranged components than those shown inFIG.6. Additionally, or alternatively, a set of components (e.g., one or more components) of device600may perform one or more functions described as being performed by another set of components of device600.

FIG.7is a flowchart of an example process700associated with transferring a reticle to a reticle carrier described herein. In some implementations, one or more process blocks ofFIG.7may be performed by one or more devices and/or tools (e.g., one or more of the exposure tool102, the load port104, the interface tool108, the reticle transport device114, and/or the reticle transport device118). Additionally, or alternatively, one or more process blocks ofFIG.7may be performed by one or more components of device600, such as processor620, memory630, storage component640, input component650, output component660, and/or communication component670.

As shown inFIG.7, process700may include retrieving a reticle from an electrostatic chuck of an exposure tool (block710). For example, the exposure tool102may use the exchanging station122to retrieve the reticle216from an electrostatic chuck (e.g., the reticle stage124) of the exposure tool102, as described above.

As further shown inFIG.7, process700may include positioning the reticle on a plurality of support pins included on a baseplate of a reticle carrier (block720). For example, the exposure tool102may use the exchanging station122to position the reticle216on a plurality of support pins (e.g., the support pins304and/or404) included on the inner baseplate214of the reticle carrier106, as described above. In some implementations, a residual charge on the reticle216from the electrostatic chuck is discharged through the plurality of support pins when the reticle216is positioned on the plurality of support pins. In some implementations, a distance (d1, d4) between the reticle216and the inner baseplate214is configured to prevent attraction of particles314equal to or greater than a threshold particle size from the inner baseplate214to the reticle216.

As further shown inFIG.7, process700may include positioning a cover of the reticle carrier over the reticle such that the reticle is enclosed in an inner space formed between the cover and the baseplate (block730). For example, the exposure tool102may use the reticle transport device118to position the inner cover212of the reticle carrier106over the reticle216such that the reticle216is enclosed in an inner space (e.g., the inner space302and/or402) formed between the inner cover212and the inner baseplate214, as described above.

Process700may include additional implementations, such as any single implementation or any combination of implementations described below and/or in connection with one or more other processes described elsewhere herein.

In a first implementation, the distance (d1) between the reticle216and the inner baseplate214corresponds to the height (h1) of the plurality of support pins304. In a second implementation, alone or in combination with the first implementation, the distance (d4) between the reticle216and the inner baseplate214corresponds to a combination of the height (h2) of the plurality of support pins404and the depth (d2) of the recessed region412in the inner baseplate214. In a third implementation, alone or in combination with one or more of the first and second implementations, the distance (d1, d4) between the reticle216and the inner baseplate214is configured to satisfy a discharge rate parameter associated with the reticle216.

In a fourth implementation, alone or in combination with one or more of the first through third implementations, the distance (d1, d4) between the reticle216and the inner baseplate214is configured to satisfy a capacitance parameter associated with the reticle216and the inner baseplate214.

AlthoughFIG.7shows example blocks of process700, in some implementations, process700may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted inFIG.7. Additionally, or alternatively, two or more of the blocks of process700may be performed in parallel.

FIG.8is a flowchart of an example process800associated with forming a reticle carrier described herein. In some implementations, one or more process blocks ofFIG.8may be performed by one or more manufacturing devices and/or systems. Additionally, or alternatively, one or more process blocks ofFIG.8may be performed by one or more components of device600, such as processor620, memory630, storage component640, input component650, output component660, and/or communication component670.

As shown inFIG.8, process800may include forming a cover of a reticle carrier (block810). For example, the inner cover212of the reticle carrier106may be formed by casting, molding, machining (e.g., computer numerical control (CNC) machining or milling), extruding, three-dimensional (3D) printing or another type of additive manufacturing (e.g., direct metal laser sintering (DMLS)), laser cutting or water jet cutting, forging, injection, thermoforming, welding, and/or another manufacturing technique.

As further shown inFIG.8, process800may include forming a baseplate of the reticle carrier (block820). For example, the inner baseplate214of the reticle carrier106may be formed by casting, molding, machining (e.g., CNC machining or milling), extruding, 3D printing or another type of additive manufacturing (e.g., DMLS), laser cutting or water jet cutting, forging, injection, thermoforming, welding, and/or another manufacturing technique. In some implementations, the inner cover212and the inner baseplate214are configured to be coupled to form an inner space (e.g., an inner space302and/or402) of the reticle carrier106.

As further shown inFIG.8, process800may include forming a plurality of support pins on the baseplate (block830). For example, the plurality of support pins (e.g., the support pins304and/or404) on the inner baseplate214may be formed by casting, molding, machining (e.g., CNC machining or milling), extruding, 3D printing or another type of additive manufacturing (e.g., DMLS), laser cutting or water jet cutting, forging, injection, thermoforming, welding, and/or another manufacturing technique. In some implementations, at least one of the inner baseplate214or the plurality of support pins are formed based on a threshold particle size to prevent particles314equal to or greater than the threshold particle size from being electrostatically attracted to the reticle216that is to be stored in the reticle carrier106.

Process800may include additional implementations, such as any single implementation or any combination of implementations described below and/or in connection with one or more other processes described elsewhere herein.

In a first implementation, process800includes determining (e.g., by the device600using the processor620) the threshold particle size to prevent the particles314equal to or greater than the threshold particle size from being electrostatically attracted to the reticle216. In a second implementation, alone or in combination with the first implementation, forming the inner baseplate214includes forming the recessed region412in a portion of the inner baseplate214based on the threshold particle size to satisfy a capacitance threshold for a capacitance between the inner baseplate214and the reticle216.

In a third implementation, alone or in combination with one or more of the first and second implementations, forming the recessed region412includes forming a first portion of the recessed region412, that is between a first support pin404aand a second support pin404bof the plurality of support pins404, to the first width (w1) in a range of approximately 130 millimeters to approximately 140 millimeters, and forming a second portion of the recessed region412, that is not in between the first support pin404aand the second support pin404b, to the second width (w2) in a range of approximately 140 millimeters to approximately 155 millimeters.

In a fourth implementation, alone or in combination with one or more of the first through third implementations, process800includes determining (e.g., by the device600using the processor620) an electrostatic force threshold for attracting particles314equal to the threshold particle size to the reticle216, determining an electric field magnitude, for an estimated electric field between the inner baseplate214and the reticle216, such that the electrostatic force threshold is not satisfied, and determining (e.g., by the device600using the processor620) a distance (d1, d4) between the inner baseplate214and the reticle216based on the electric field magnitude.

In a fifth implementation, alone or in combination with one or more of the first through fourth implementations, forming the inner baseplate214includes forming the inner baseplate214to satisfy the distance (d1, d4). In a sixth implementation, alone or in combination with one or more of the first through fifth implementations, forming the plurality of support pins includes forming the plurality of support pins to satisfy the distance (d1, d4). In a seventh implementation, alone or in combination with one or more of the first through sixth implementations, the distance (d1, d4) is in a range of approximately 1150 microns to approximately 4000 microns.

AlthoughFIG.8shows example blocks of process800, in some implementations, process800may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted inFIG.8. Additionally, or alternatively, two or more of the blocks of process800may be performed in parallel.

In this way, a reticle carrier described herein is configured to quickly discharge the residual charge on a reticle so as to reduce, minimize, and/or prevent particles in the reticle carrier from being attracted to and/or transferred to the reticle. In particular, the reticle carrier may be configured to provide reduced capacitance between an inner baseplate of the reticle carrier and the reticle. The reduction in capacitance may reduce the resistance-capacitance (RC) time constant for discharging the residual charge on the reticle, which may increase the discharge speed for discharging the residual charge through support pins of the reticle carrier. The increase in discharge speed may reduce the likelihood that an electrostatic force in the reticle carrier may attract particles in the reticle carrier to the reticle. This may reduce pattern defects transferred to substrates that are patterned using the reticle, may increase semiconductor device manufacturing quality and yield, and may reduce scrap and rework of semiconductor devices and/or wafers.

As described in greater detail above, some implementations described herein provide a method. The method includes retrieving a reticle from an electrostatic chuck of an exposure tool. The method includes positioning the reticle on a plurality of support pins included on a baseplate of a reticle carrier, where a residual charge on the reticle from the electrostatic chuck is discharged through the plurality of support pins when the reticle is positioned on the plurality of support pins, and where a distance between the reticle and the baseplate is configured to prevent attraction of particles equal to or greater than a threshold particle size from the reticle carrier to the reticle. The method includes positioning a cover of the reticle carrier over the reticle such that the reticle is enclosed in an inner space formed between the cover and the baseplate.

As described in greater detail above, some implementations described herein provide a reticle carrier. The reticle carrier includes a cover. The reticle carrier includes a baseplate, where the cover and the baseplate are configured to be coupled to enclose a reticle in an inner space formed by the cover and the baseplate. The reticle carrier includes a plurality of support pins, on the baseplate, configured to support the reticle in the inner space, where at least one of the baseplate or the plurality of support pins are configured to facilitate discharging of a residual charge on the reticle when the reticle is placed in the reticle carrier.

As described in greater detail above, some implementations described herein provide a method. The method includes forming a cover of a reticle carrier. The method includes forming a baseplate of the reticle carrier, where the cover and the baseplate are configured to be coupled to form an inner space of the reticle carrier. The method includes forming a plurality of support pins on the baseplate, where at least one of the baseplate or the plurality of support pins are formed based on a threshold particle size to prevent particles equal to or greater than the threshold particle size from being electrostatically attracted to a reticle that is to be stored in the reticle carrier.

The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.