Abstract:
A battery powered sensing device for diagnosing a processing system and method for using the same are provided. The support platform generally has physical characteristics, such as size, profile height, mass, flexibility and/or strength, substantially similar to those of the substrates that are to be processed in the processing system, so the sensor device can be transferred through the processing system in a manner similar to the manner in which production substrates are transferred through the processing system.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 11/427,376, filed Jun. 29, 2006, which is a continuation of U.S. patent application Ser. No. 11/052,161, filed Feb. 7, 2005, which a continuation of U.S. patent application Ser. No. 10/445,598, filed May 27, 2003, now U.S. Pat. No. 6,895,831 which is a continuation of U.S. patent application Ser. No. 10/083,899, filed Feb. 27, 2002 and issued as U.S. Pat. No. 6,677,166, and U.S. patent application Ser. No. 10/084,290, filed Feb. 27, 2002 and issued as U.S. Pat. No. 6,642,853, which are divisional applications of U.S. patent application Ser. No. 09/816,806, filed Mar. 23, 2001 and issued as U.S. Pat. No. 6,468,816, which is a divisional application of U.S. patent application Ser. No. 09/036,247, filed Mar. 6, 1998 and issued as U.S. Pat. No. 6,244,121. All of the above are hereby incorporated by reference in their entireties. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to methods and apparatuses for testing or aligning the various parts of a processing system. Specifically, the present invention relates to methods and apparatuses for leveling and aligning the processing system and the various structures within the processing system that support and/or transfer processing objects, such as substrates, through the processing system so that the processing system and each structure is substantially level and so that each structure receives, supports and/or transfers the substrates in substantially the same inclination and without slippage of or damage to the substrates. 
     2. Background of the Related Art 
     Processing systems for processing 100 mm, 200 mm, 300 mm or other diameter substrates are generally known. Typically, such processing systems have a centralized transfer chamber mounted on a monolith platform. The transfer chamber is the center of activity for the movement of substrates being processed in the system. One or more process chambers mount on the transfer chamber at slit valves through which substrates are passed by a substrate handler, or robot. Access to the transfer chamber from the clean ambient environment is typically through one or more load lock chambers attached at other slit valves. The load lock chambers may open to a very clean room, referred to as the white area, or to an optional substrate handling chamber, typically referred to as a mini-environment. 
     In addition to the substrate handler disposed within the transfer chamber, a processing system may have several other structures, including, but not limited to, indexers in the load lock chambers, lift pins in the process chambers, and substrate chucks in the process chambers, which will support or handle the substrates in one manner or another. The lift and support structures within the processing system may exchange substrates more rapidly, without slippage or backside contamination of the substrates, if the lift and support structures are level. Additionally, the extremely fine and delicate nature of the circuits and other structures being constructed on the substrates may require that the processing system as a whole, and particularly each substrate support structure, be set as near to level as possible. Typically, assemblers or operators of the processing systems may try to ensure that, at a minimum, the various substrate support structures are in alignment relative to each other, so that even if each support structure is not perfectly level, at least they are all at the same inclination. Additionally, the assemblers or operators will attempt to ensure that the substrate support structures, which move the substrates laterally, accelerate and decelerate at suitable rates and without discontinuous, or jerking, motion, so that the substrates do not slip on the support structure. Failure to ensure that the processing system and/or each of the substrate support structures is properly level and/or aligned and is operating smoothly may cause damage to or improper processing of the substrates and can reduce the throughput of the processing system since substrate exchanges may not be performed at maximum speed. 
     Relative alignment of the substrate support structures is typically more important than absolute leveling of the entire processing system since substrate exchange handling can result in significant slippage due to improper alignment. When the substrate support structures, within a processing system, are improperly aligned, however, the support structures do not hold the substrates at about the same inclination, or tilt. Thus, when one support structure transfers a substrate to another support structure, such as when the lift pins remove a substrate from a blade of the transfer chamber substrate handler or place a substrate onto the substrate chuck in a process chamber, one point of the substrate will always touch the receiving support structure before other points do. If substantial motion occurs prior to the remaining points making contact, then the substrate can slip. In this manner, potentially contaminating particles may be scraped from the contacting points of the substrate causing backside contamination of the substrate. These particles may eventually work their way around to the top of the substrate and be deposited on the processed surface of the substrate, thereby contaminating the micro circuits or other structures constructed thereon. Additionally, when the substrate does not touch a receiving support structure with all points in very close alignment, then the substrate may be shifted from its proper, or expected, position, so that the substrate is off-center. An off-center substrate may undergo uneven or otherwise improper processing or may come in contact with surfaces or objects within the processing system that will contaminate the substrate, create potentially contaminating airborne particles or even break the substrate. Thus, exchanges of the substrate between lifting or supporting structures within the processing system require a coplanar interface. If the exchange is not coplanar, then the substrate will have the propensity to slip, resulting in misalignment and backside contamination of the substrate. 
     When a processing system as a whole is improperly leveled, the system chambers, such as the transfer chamber, are inclined at an angle and can cause problems with the handling and processing of substrates and can exacerbate the problems with substrate support structures that are further inclined relative to the processing system. Since the substrate support structures are mounted to the processing system, if the processing system is inclined and the support structures are level relative to the processing system, then the support structures will also be inclined, though the support structures may, nevertheless, be aligned with each other. When the processing system is inclined, but the support structures are aligned, then the processing system may still operate properly, but possibly at a lower than optimum speed. Additionally, performance of certain functions that are sensitive to gravity may be affected by the inclination of the system. When a transfer chamber substrate handler, for example, accelerates a substrate in a manner that may be appropriate for a level system, the substrate may, nevertheless, slide off-center due to the inclination, thereby exposing the substrate to potential damage from particles that may be generated by the slide or to potential collision with a surface or object in the processing system that requires a relatively close centering tolerance of the substrate for clearance. 
     The substrate support structures typically may be leveled independently within the processing system. Thus, after the transfer chamber and the processing chambers are leveled as a whole, the transfer chamber substrate handler or the process chamber lift pins or chuck may be additionally leveled independently. It is even possible for a substrate handler to be fairly level while the transfer chamber is significantly inclined, or vice versa. In such manner, the substrate handler may be aligned with an opening through which it passes substrates to and from a process chamber on one side of the transfer chamber, yet be out of alignment with an opening for a process chamber on the opposite side of the transfer chamber. Therefore, the transfer chamber substrate handler must be fairly closely aligned with the inclination of the transfer chamber to permit proper functioning of the entire system. 
       FIG. 1   a  shows a prior art method of determining the inclination of a transfer chamber substrate handler  10 . The transfer chamber  12  is shown with a lid  14  partially lifted to expose the interior of the chamber body  16 . The substrate handler  10  is mounted in about the center of the transfer chamber  12  and rotates about a center point. The substrate handler  10  extends a blade  18  to insert a substrate  20  through a slit valve opening  22  to access a process chamber (not shown) or a load lock chamber (not shown) mounted to the facets  24 . To determine the inclination of the blade  18 , an operator places a level, such as a bubble level,  26  onto the blade  18  and reads the inclination through a window in the level  26 . The level  26  may be placed directly onto the blade  18 , or the level  26  may be placed onto a substrate  20  sitting on the blade  18 . The inclination of the blade  18  must be measured in each relevant direction with the blade  18  retracted as shown and with the blade  18  extended through the slit valve  22 , so the substrate handler  10  can function properly throughout all of its movements. The actual leveling of the substrate handler  10  may involve adjusting the transfer chamber  12  relative to a support platform (not shown), adjusting the base  28  relative to the transfer chamber  12  and adjusting the arms  30 , linkages  32  and blade wrist  34 . 
     There are several problems with the measurement method depicted in  FIG. 1   a.  The substrate handler  10  must be still, for example, so the operator can read the level  26 , since the acceleration of the blade  18  would affect the level  26 . Therefore, the inclination of the blade  18  while the blade is in motion is unknown. Additionally, the lid  14  must be removed, so the operator can access the substrate handler  10 . Therefore, the processing system must be shut down, so the lid  14  can be removed, intruding into the clean environment; and the ambient air must be more highly filtered of particles than usual, so the interior of the transfer chamber  12  is not contaminated. Also, the level  26  does not fit through the slit valve openings  22 , so the operator must remove the level  26  from the blade  18  to extend the blade  18  into a process chamber and then place the level  26  back onto the blade  18 . Therefore, the process chamber must also be opened, exposing the process chamber to possible contamination and further increasing the down-time of the system. Furthermore, the levels used to measure the inclination typically can resolve the inclination to within only two or three degrees accuracy, are highly dependent on the skill of the operator who is reading the level, and can affect the blade deflection due to the weight of the level, itself. Therefore, process systems or processes that are particularly sensitive to misalignment may be adversely affected. Because of the problems and difficulties with performing this measurement method, some operators may elect not to make these measurements very thoroughly or even not to make them at all. 
       FIG. 1   b  shows another prior art method for determining the inclination of a substrate  20  seated on a substrate handler blade  18  within a processing system. A stationary laser  36  mounts to a surface  38  in the processing system, typically the floor of the transfer chamber, and directs a laser beam  40  into the path of the substrate  20  as the substrate moves through the system in the direction of arrow A. This method may be performed during normal processing of substrates in the processing system or just whenever needed. When the leading edge  42  of the substrate  20  intersects the laser beam  40 , the laser  36  detects the distance to the substrate  20 . Then just before the trailing edge  44  moves out of the laser beam  40 , the laser  36  detects the distance to the substrate  20 , again. If the two distances are about the same, then the substrate  20  is aligned with the surface  38  of the processing system in the particular axis measured. However, this method does not determine if the substrate  20  is level. Rather, this method determines the alignment of the substrate  20  relative to the chamber through which it is being transferred, so the problems with an inclined substrate  20  or blade  18 , as described above, may still occur. Additionally, this method can determine the inclination of the substrate  20  in only one axis, the direction of movement. Since the laser  36  does not move, if the operator wants to determine the inclination of the substrate  20  in a different axis, then one or more other lasers will have to be mounted in the processing system to determine the distance to other points on the substrate  20 . Furthermore, since the laser  36  is not moveable, this method determines the inclination of the substrate  20  at only one location, so if the operator wants to determine the inclination of the substrate  20  at a different location, such as at the opposite side of the transfer chamber, then additional lasers will have to be mounted at that location. Moreover, since the laser  36  is mounted into the processing system, removal of the laser  36  is either impossible or very difficult. Additionally, contaminants may prevent the proper functioning of the optics. Furthermore, a warped substrate may lead the laser sensors to incorrectly determine that the blade or substrate is inclined. Therefore, although this method can be performed without opening the processing system, this method is very inflexible. 
     During processing, the blade  18  in many processing systems is constantly moving between areas of high and low temperatures, such as hot process chambers and cool load lock chambers. The frequent temperature variations may cause the blade  18  to suffer “blade wilt,” wherein the blade  18  becomes warped due to expansion and shrinkage resulting from the temperature changes. Thus, over time, the blade  18  may be warped out of alignment, so the blade  18  may degrade and hold the substrates at an unacceptable inclination. Other shifting of alignments between the various substrate support structures, due to the wear or slippage from constant movement during processing, may also occur. To reestablish confidence in the alignment of the substrate support structures, the processing system must have built-in inclination detection systems, such as the one shown in  FIG. 1   b,  or the operator must stop the processing system and open it up to diagnose the condition of the support structures with a method such as the one shown in  FIG. 1   a.  Because of the down-time associated with the method shown in  FIG. 1   a,  many operators elect not to perform the method or to wait until the substrate support structures are severely out of alignment and potentially damaging the substrates. 
     Therefore, a need exists for an apparatus and method for determining the inclination and alignment of various substrate handling mechanisms of a processing system, but that is very flexible, does not intrude into the clean environment of the processing system, is fast, and provides a very thorough diagnosis of the system alignments. 
     SUMMARY OF THE INVENTION  
     A battery powered sensing device for diagnosing a processing system and method for using the same are provided. The support platform generally has physical characteristics, such as size, profile height, mass, flexibility and/or strength, substantially similar to those of the substrates that are to be processed in the processing system, so the sensor device can be transferred through the processing system in a manner similar to the manner in which production substrates are transferred through the processing system. 
     In one embodiment, an apparatus for obtaining information from within a processing system includes a battery powered sensing device sized for robotic transfer between a central transfer chamber and a vacuum processing chamber of the processing system, wherein the device is configured for obtaining information of a condition within the processing system. 
     In another embodiment, a method of obtaining information from within a processing system includes robotically moving a battery powered sensing device through a slit valve disposed between a central transfer chamber and a vacuum processing chamber of a processing system, and obtaining, via the sensing device, information of a condition within the processing system. 
     Another embodiment of the present invention may be a sensor device generally having a support platform and one or more sensors mounted on the support platform. The sensor senses a condition, such as direction or inclination or acceleration in one or two axes, of the sensor device and outputs a signal indicative thereof. The sensor sends the signal to a conversion circuit, such as an analog-to-digital converter, for converting the signal into a digital signal, which is then sent to a transmitter, also mounted to the support platform, for wireless transmission of the signal to a receiver mounted on or near the processing system. 
     The support platform generally has physical characteristics, such as size, mass and stiffness, substantially similar to those of the substrates being processed in the processing system, so the sensor device can be transferred throughout the processing system in a manner similar to the manner in which production substrates are transferred. Thus, the sensor device is conveyed through the processing system non-intrusively, i.e. without opening the isolated portions of the system. Also, the sensor device, while moving through the processing system, detects and transmits the sensed inclination, orientation or other information. 
     The support platform may be a substrate, and the sensor(s) and other circuits/devices on the support platform may be micro-machined directly into the material of the substrate to form a low-profile sensor device having a total mass near the mass of a production substrate. In an alternative embodiment, a ceramic chip carrier may be mounted to the support platform, with a die for the sensor(s) and other circuits/devices formed into the ceramic chip carrier to provide a fairly light-weight and cost-effective sensor device. In yet another alternative embodiment, the sensor(s) and other circuits/devices may be constructed of surface-mount integrated circuit chips mounted to the support platform to provide a cost-effective sensor device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. 
       It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
         FIG. 1   a  is a perspective view of a prior art sensor device in a process chamber. 
         FIG. 1   b  is a side view of a prior art sensor system. 
         FIG. 2   a  is a perspective view of a processing system. 
         FIG. 2   b  is a schematic top view of a processing system. 
         FIG. 3  is a schematic block diagram of a sensor device. 
         FIG. 4  is a perspective view of a sensor device in a transfer chamber. 
         FIG. 5  is a perspective view of a sensor device on a substrate handler. 
         FIG. 6  is a top view of a sensor device on another substrate handler. 
         FIG. 7   a  is a side view of a sensor device in a process chamber in a first configuration. 
         FIG. 7   b  is a side view of the sensor device in the process chamber in a second configuration. 
         FIG. 8  is a graph of the velocity of the sensor device during movement. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIGS. 2   a  and  2   b  show two configurations for an exemplary processing system  100  of the present invention. The processing system  100  is typically disposed in a clean environment of a manufacturing facility. The processing system  100  and an example of its function will be described in detail below. Generally, the processing system  100  includes a central transfer chamber  112 , one or more process chambers  114 , one or more load lock chambers  118 , one or more expansion or cool-down chambers  119 , a platform frame  121 , a gas panel  124  and an optional external substrate handling system  120 , referred to herein as the mini-environment. Some of the processes that a processing system  100  may perform on a substrate, or wafer, in the process chambers  114  require the use of process fluids and/or gases, so the process chambers  114  have fluid lines (not shown) for delivering the process fluids and/or gases to the process chambers  114  from the gas panel  124 . A transfer chamber substrate handler, or robot,  116  and a mini-environment substrate handler  128  are disposed in the transfer chamber  112  and mini-environment  120 , respectively, and move substrates  117 ,  156  through these chambers to and from the various chambers attached thereto. 
     The substrates enter the process system  100  from pod loaders  122  having pods  154  seated thereon containing several substrates  156 . Several structures, such as the substrate handlers  116 ,  128 , chucks, lift pins, load lock indexers and the like, support the substrates as the substrates are moved through and processed in the system  100 . To prevent damage to or improper processing of the substrates, the inclination of each of the support structures must be very closely aligned and leveled, and the movement of the support structures and substrates must be smooth. To determine the inclination and movement of the substrates without shutting down the system  100  for a significant period of time and opening up the system  100  to expose the interior of the system  100  to potential contamination, a sensor device  200  ( FIG. 3 ) is entered into the system  100  from a pod loader  122  and transferred through the system  100  in a manner similar to the manner that the system  100  handles the substrates, i.e. production substrates, that are to be processed. The sensor device  200  is an active probe which can be entered into the system  100  to investigate many aspects or conditions of the system  100 . The sensor device  200  generally includes a support platform  202  and several electronic devices, such as an inclinometer  204 , an accelerometer  206 , a directional compass  208 , an analog to digital (A/D) converter  210 , a transmitter  212 , a power source  214  and a switch  216 . In addition, a small processor (not shown) for pre-filtering data may be incorporated in the circuitry. 
     In the illustrated embodiment, the inclinometer  204  mounts to the support platform and senses the inclination of the sensor device  200  and, hence, of the substrate handler or other support structure. The inclinometer  204  receives electrical power from the power source  214 , such as a lithium-ion battery and power conditioner, and sends signals indicative of the sensed inclination to the A/D converter  210 . In one embodiment, the inclinometer  204  is a two-axis inclinometer for sensing the inclination of the sensor device  200  in two axes at 90°, so the overall inclination of the sensor device  200  can be determined from a suitable calculation. After initial assembly of the processing system  100 , the sensor device  200  can be used to adjust the inclination of each support structure by transferring the sensor device  200  through the processing system  100  to each support structure, sensing the inclination of each support structure at the time that the sensor device  200  is disposed thereon and adjusting each support structure as described below to align each support structure. As described in the background, a misalignment between two support structures can cause particles to be generated or can result in an uncertain positioning of the substrate when one of the support structures transfers a substrate to the other support structure, so proper alignment of the support structures is essential. 
     An exemplary inclinometer  204  includes a cavity partially filled with a conductive fluid, such as mercury, and an array of probes disposed vertically in the cavity into the conductive fluid. As the inclinometer  204  inclines, the probe at one end of the array will have a greater contact, and less resistance, with the conductive fluid than will the probe at the opposite end of the array. The variation in resistances sensed at each of the probes determines the inclination of the inclinometer  204 . Such inclinometers, having a profile height of about ½ inches, are commercially available and can sense an inclination of up to about thirty to forty degrees. However, the inclinometer  204  needs to be able to sense an angle of only about five to ten degrees, since the typical processing system  100  can generally be assembled in such a manner that the inclination of any given support structure is within this range. Therefore, a suitable inclinometer  204  may be constructed having a mass and profile height significantly less than currently available inclinometers. It is understood that the invention is not limited to the type of inclinometer described, but rather, contemplates the use of any suitable inclinometer. 
     The accelerometer  206  mounts to the support platform and senses the acceleration of the sensor device  200  and, hence, of the substrate handler or other support structure. The accelerometer  206  receives electrical power from the power source  214  and sends signals indicative of the sensed acceleration to the A/D converter  210 . In one embodiment, the accelerometer  206  is a two-axis accelerometer for sensing the acceleration of the sensor device  200  in two axes, so the overall acceleration of the sensor device  200  can be determined from a suitable calculation. Similar to the inclinometer  204 , the accelerometer  206  senses the acceleration, or change in motion, of the sensor device  200  while the processing system  100  transfers the sensor device  200 . For best throughput, the substrate handlers need to be operated at the highest speed possible, but an acceleration in a particular axis that is too great for static friction to hold a substrate on a moving support structure, about 0.2 G&#39;s or greater, may indicate a potential for slippage of the substrate on the support structure during movement, resulting in an uncertain positioning of the substrate, further resulting in damage to or improper processing of the substrate. Actual slippage of the sensor device  200  or malfunctioning of a substrate handler  116 ,  128  may be determined by the sensor device  200  when the sensed acceleration of the sensor device  200  is not substantially the same as the anticipated acceleration during a particular movement, indicating that the sensor device  200  did not move in the same manner as the substrate handler  116 ,  128  or the substrate handler  116 ,  128  moved in an unanticipated manner, such as a jerking, irregular movement.  FIG. 8  graphically illustrates such an irregular movement. The graphed curve is velocity plotted versus time; however, other plots, such as acceleration vs. time or inclination vs. time, may be used. In regions  800  and  804 , the velocity smoothly increases until it reaches a constant velocity and then smoothly decreases, but in region  802 , an irregular movement causes a sharp rise, or discontinuity, in the curve, indicating a problem with the movement of the substrate handler  116 ,  128 . Thus, the sensor device  200  can detect an improper movement by a substrate handler  116 ,  128 . 
     In an alternative embodiment, the inclinometer  204  may determine the acceleration of the sensor device, instead of by a separate accelerometer; thereby, reducing the number of devices on the sensor device  200 . The inclinometer  204  described above includes a fluid in a cavity, so as the inclinometer  204  is accelerated, the force of acceleration on the fluid will force the fluid to one end of the cavity; thereby, falsely indicating an inclination of the sensor device in the direction of acceleration. A suitable procedure can resolve this false inclination to an acceleration. 
     The directional compass  208  provides the ability of the sensor device  200  to determine the horizontal angle, or compass direction, of the sensor device  200  from magnetic north. Thus, as the substrate handler  116 ,  128  or other support structure moves the sensor device through the system  100 , the compass direction of the sensor device  200  can be determined at any point in the trajectory of the sensor device. The anticipated compass direction of the sensor device  200  can be compared with the actual compass direction to confirm proper movement of the sensor device  200 . Additionally, the inclination of the entire system  100  can be determined by determining the inclination of the sensor device  200  at corresponding compass direction points as the substrate handler  116  rotates about a 360° angle. With this data, the inclination of the system  100  can be resolved with a suitable procedure. 
     The A/D converter  210  receives the analog signals from each of the devices  204 ,  206 ,  208  and converts the signals into digital signals, which are then packetized for transmission via the transmitter  212  to a receiver. Other methods and apparatuses for transferring the signals from the sensor device  200  will be readily apparent to a person skilled in the art. Such other methods and apparatuses may include, but not be limited to, a transmission system for sending the analog signals to a receiver, so as to save the weight of the A/D converter  210  on the sensor device  200 . 
     The transmitter  212  may be any appropriate transmitter device, such as an optical transmitter or RF based transmitter, for sending signals the relatively short distance from the interior of the system  100  to the exterior. Thus, the transmitter  212  may be an inexpensive low-power transmitter device. 
     One or more receivers  218  are mounted on the system  100  to receive the signals from the transmitter  212  and send the signals to a controller system for the system  100 . The receivers may be located on the interior of the system  100  and send the signals over wires through the walls of the system  100 . However, to avoid having to modify the system  100  for wires to pass through the system walls, it is preferred that the receivers  218  be located on the exterior of the system  100  at any appropriate aperture, such as at the viewing ports  220  in the lid of the transfer chamber  112  ( FIG. 4 ), where RF signals can be conveyed out of the system  100  with a minimum of interference. 
     The power source  214  may be any appropriate device, such as a lithium-ion battery in conjunction with a power conditioner for obtaining proper working voltages, which is light-weight and provides sufficient power for sufficient time to conduct all of the measurements necessary for the system  100 . The battery may be rechargeable for repeated use, or it may be replaceable in a suitable receptacle. The switch  216  turns the power on and off to the electronic devices on the sensor device  200 . 
     It is understood that the invention is not limited to the sensor device  200  depicted in  FIG. 3  and described herein, but contemplates other configurations of sensor devices or active probes, including but not limited to the examples described below, that may be transferred through a processing system and may have any number of different combinations and types of electronic devices for sensing conditions within the system  100 . For example, a magnetic probe that includes hall effect magnetic field sensors may allow magnetic fields to be characterized within the system  100  while the system  100  is closed. Thus, an operator may adjust the rotation of a magnetron or the current flowing through a variety of coils in a process chamber to ensure uniformity of magnetic fields created therein and of a plasma created thereby within the process chamber while receiving immediate feedback of the actual conditions of the fields. 
     Another type of probe may provide characterization of an electrostatic chuck, which holds a substrate in place using an electrostatic charge during processing. This probe may determine the performance of various charge abatement strategies used to release the substrate so the substrate may be picked up and removed by a substrate handler. The probe may also detect dielectric punch-throughs, a condition in which charge differential between the electrostatic chuck and the substrate is lost due to discharge holes in the non-conductive face of the electrostatic chuck. One embodiment of such an electrostatic probe has a micro machine and/or circuit on a substrate platform including a diaphragm element which deflects toward the electrostatic chuck as a function of charge. The magnitude of this deflection indicates the charge differential between the probe/substrate and the electrostatic chuck. The electronic devices on the electrostatic probe must be fabricated to withstand the environment adjacent the electrostatic chuck since this environment is usually hostile to active electronics. 
     Yet another probe may be a temperature probe including temperature sensors to map thermal characteristic of an environment inside the system  100 . Many process chambers and systems  100  operate at very high temperatures, such as above 300° C., so since most electronics only work up to about 80° C., the probe may only be used if the system  100  is operated at a lower temperature. The temperature probe may be used to develop or validate basic temperature control schemes within the system  100  or individual process chambers. Additionally, a temperature probe which can detect a thermal gradient across the length of the probe may determine uniformity of process gas distribution within a process chamber since a small gradient indicates that the process gas has been evenly distributed over the probe. The thermal gradient probe must account for disruptions in the normal flow of the process gases due to any structures on the surface probe. For use in a process chamber having a shower head gas inlet at the top of the process chamber and which can rotate a substrate for even processing, such as in some chemical vapor deposition chambers, a configuration for a temperature probe includes an array of temperature sensors on the probe platform orientated radially out from the center thereof with spacing matching the spacing of the gas apertures of the shower head. As the probe is rotated, it can detect a change in temperature associated with the gas exiting each aperture, so clogged apertures may be detected by an unexpected temperature variation. An embodiment for this example may include piezoelectric detectors which deflect when subjected to the gas stream in front of the aperture. 
     Another active probe is a distance probe which can ensure that the wafer surface is both parallel to and at the proper distance from the target or shower head of the process chamber. Embodiments of a distance probe may include contacting sensors or electro-optical sensors arranged at a sufficient number of locations on the surface of the probe platform to determine the distance from and angle of inclination between the probe and the target or shower head. Since the distance probe sits on a chuck in the process chamber when the distance measurements are performed, the mass of the probe is not a significant issue, so the weight of the distance probe may be increased if necessary to reduce the cost. 
     Yet another type of probe may be an optical source detection probe for detecting a light beam, infrared beam or other optical signal from a source thereof to determine whether the source is operating within normal or acceptable limits. Such optical sources may be part of an optical sensor system within a system  100  for providing feedback to a system controller regarding the performance of parts of the system  100 , such as a substrate edge detection sensor system for automatic center finding of substrates being processed within the system  100 . If the optical source detection probe determines that a source is not operating within acceptable limits, then the optical source may be defective or the optical pathway of the optical beam signal from the source may be contaminated or blocked, so the system  100  may require servicing or maintenance. 
       FIG. 4  shows a sensor device  200  positioned on the substrate handler  116  inside the transfer chamber  112  with the transfer chamber lid  240  partially raised. The substrate handler  116  moves the sensor device  200  back and forth in the directions of arrows A and B and/or holds the sensor device  200  relatively motionless at any location inside the transfer chamber  112  while the sensor device  200  takes the desired measurements and transmits the information to the receivers  218  positioned on the exterior of the transfer chamber  112 . 
       FIGS. 5 and 6  show two different types, single bladed and double bladed, of substrate handlers  116  for illustrative purposes; however, both substrate handlers  116  perform the functions of rotating the sensor device  200  within the transfer chamber  112  and extending the sensor device  200 ′, as shown by the dashed lines in  FIG. 6 . The substrate handler  116  has a blade  244  for holding the sensor device  200 . The blade  244  attaches at a wrist  258  to articulating arms  254 ,  256 , which attach to actuating arms  246 ,  248 , which attach to upper and lower rotating members  250 ,  252 , respectively, to rotate back and forth to rotate the sensor device  200  and/or to extend or retract the sensor device  200 . Each joint of the substrate handler  116  must be carefully aligned for the movement of the sensor device  200  to be proper. In other words, the blade  244  must be properly attached and aligned to the articulating arms  254 ,  256  at the wrist  258 , the articulating arms  254 ,  256  must be properly aligned with respect to the actuating arms  246 ,  248 , and the actuating arms  246 ,  248  must be properly aligned with the upper and lower rotating members  250 ,  252  for the inclination of the blade  244  to be proper. Any misalignment in any of the joints of the substrate handler  116 , or in the alignment between the substrate handler base  260  and the transfer chamber floor  262 , can cause the blade  244  to be improperly inclined, and the inclination can be detected by the sensor device  200 . 
     Mechanical tolerances and mechanical pre-loads in each of the joints of the substrate handler  116  can make accurate alignment of the blade  244  extremely difficult. Thus, it is very undesirable to have to replace and realign the blade  244 . However, the blade  244  is subjected to many rapid variations in temperature during operation of the system  100 , so the blade  244  may undergo blade wilt, or warpage, causing the blade to become inclined or the attachment points at the wrist  258  to yield. If the blade inclination or attachment point yield becomes severe, then the blade  244  or a substrate on the blade  244  may strike an object or surface in the system  100 ; thereby breaking or otherwise damaging the blade  244  or the substrate. In such an event, the system  100  will have to be turned off and opened to repair or replace the damaged parts, including the blade  244 . If the blade  244  is broken, then the wrist  258  or other parts and joints of the substrate handler  116  may be compromised or damaged, so each part of the substrate handler  116  will have to be realigned. To prevent this damage and downtime, the inclination and alignment of the blade  244  should be confirmed periodically. The sensor device  200  provides a way to confirm the inclination and alignment of the blade  244  in all directions without having to turn off and open the system  100 ; thereby, permitting detection and replacement of a wilted or defective blade before severe damage occurs. 
     The substrate handler  116  extends, as shown in  FIG. 6 , to insert the sensor device  200  through a slit valve opening  242  and into an attached process chamber (not shown). The height of the sensor device  200  and all of the electronic devices thereon is such that the sensor device  200  can easily pass through the slit valve opening  242  while seated on the blade  244 . Thus, the sensor device  200  can determine the inclination at the retracted position, extended position or any intermediate position without having to remove the sensor device  200 , insert the blade  244  through the slit valve opening  242 , and replace the sensor device  200 . The sensor device  200  can also determine the acceleration during the extension and retraction of the substrate handler  116 . 
     The operation of the sensor device  200  with a typical process chamber will now be described with reference to  FIG. 7 . Although  FIG. 7  shows a schematic view of a CVD chamber  114 , it is understood that the invention is not so limited, but that the substrate handler  116  can insert the sensor device  200  through the slit valve opening  242  into any type of process chamber  114 , such as a PVD chamber, a CVD chamber, an etch chamber, a photo lithography chamber or other chamber, and that the sensor device  200  may operate with any of these types of process chambers. The process chamber  114  generally has chamber walls  270 , a substrate lift mechanism  272 , a substrate support structure  274  and a chamber lid  278 . The chamber walls  270  and chamber lid  278  generally define the interior of the process chamber  114 . An opening  280  provides access to the interior of the process chamber  114  and matches up with the slit valve opening  242  of the transfer chamber  112  for the substrate handler  116  to insert or remove substrates into or from the interior of the process chamber  114 . A process gas shower head  276  disposed in the chamber lid  278  permits a process gas to enter through a gas source  282  and be dispersed into a processing region  286  of the interior of the process chamber  114  through shower head nozzles  284 . 
     The substrate lift mechanism  272  generally has lift pins  292  for supporting a substrate (not shown) and mounted on an arm  290  which is, in turn, mounted on a lift rod  288  for raising and lowering the substrate lift mechanism  272 . When a substrate is inserted through the opening  280  into the interior of the process chamber  114 , the lift mechanism  272  lifts the substrate off of the blade  244  of the substrate handler  116  with the lift pins  292  by raising the lift rod  288  and arm  290  as depicted in  FIG. 7   a.  The blade  244  passes between the lift pins  292  when the lift pins  292  support the substrate. The substrate lift mechanism  272  handles the sensor device  200  in the same manner as it handles a substrate. In this manner, the sensor device  200  is passed from the substrate handler  116  to the substrate lift mechanism  272 . 
     The substrate support structure  274  generally includes a chuck  294  for supporting a substrate and mounted on a lift rod  296  for raising and lowering the substrate support structure  274 . The substrate support structure  274  also has guide holes  298  for permitting the lift pins  292  to extend therethrough, as shown in  FIG. 7   a , to engage the substrate or sensor device  200 . To place the sensor device  200  onto the chuck  294 , the substrate lift mechanism  272  may lower the sensor device  200  to the chuck  294 , as shown in  FIG. 7   b , or the chuck  294  may rise up to lift the sensor device  200 . In this manner, the sensor device  200  is passed from the substrate lift mechanism  272  to the substrate support structure  274 . 
     While seated on either the substrate lift mechanism  272  or the substrate support structure  274 , the sensor device  200  can determine its inclination, just as it could when it was seated on the substrate handler  116 . Both the substrate lift mechanism  272  and the substrate support structure  274  can be individually adjusted from outside the process chamber  114  by manipulating the mechanisms (not shown) that support and operate the lift rods  288 ,  296  to tilt or swivel the lift rods  288 ,  296 , and thereby, change the inclination of the lift pins  292  or chuck  294 , respectively. Since these manipulations can be done from outside, typically underneath, the process chamber  114 , the sensor device  200  provides a means to receive feedback regarding the inclination of the substrate lift mechanism  272  and the substrate support structure  274  without opening the process chamber  114 . Thus, these structures  272 ,  274  can be leveled to correct an improper inclination very quickly and accurately. 
     Additionally, the degree of misalignment between the substrate handler  116  and the substrate lift mechanism  272  and between the substrate lift mechanism  272  and the substrate support structure  274  can be determined from a reading of the inclination of the sensor device  200  before and after a transfer from one structure to the other. Thus, the sensor device  200  provides a way to convey the inclination at exchange points and to align each structure that supports a substrate with the other such structures without opening the system  100  and compromising the isolated environment therein. In a similar manner, even though it is not shown in the drawings, the indexer cassette lift of the load lock chambers  118  ( FIG. 2 ) has a mechanism for leveling or aligning the indexer plate, which supports cassettes and/or substrates within the load lock chamber  118 . The indexer can be aligned with respect to the substrate handlers  116 ,  128 . A typical alignment procedure for aligning all of the substrate support structures within a system  100  may begin with leveling one support structure, such as whichever support structure is most difficult to adjust, e.g. the substrate handler  116 , and then aligning all other support structures with respect to the first support structure. In this manner, alignment throughout the system  100  is assured, so a substrate is unlikely to be damaged during transfers from one support structure to another. 
     A typical operation of the sensor device  200  will be described with reference to the exemplary system described below. 
     An Exemplary System 
     Referring back to  FIG. 2 , a processing system which may use the above described sensor device  200  to diagnose substrate handling conditions will now be described.  FIG. 2   a  generally shows a perspective view of a processing system  100 .  FIG. 2   b  generally shows a schematic top view thereof. Although the function of the sensor device  200  is described herein with reference to the system  100 , it is understood that the invention is not so limited, but that the sensor device  200  may function with any type of processing system. As mentioned briefly above, the processing system  100  includes a central transfer chamber  112  as the center of activity in the handling of wafers, or substrates, through the system  100 . The transfer chamber  112  typically mounts on a platform  121 . The transfer chamber  112  has process chambers  114  attached at facets  113 . The process chambers  114  may be any type of process chamber, such as a physical vapor deposition chamber, a chemical vapor deposition chamber, an etch chamber, etc. It is not uncommon for a manufacturer of process chambers to provide over twenty different types of process chambers. The process chambers  114  may be supported by the transfer chamber  112 , by the platform  121  or on their own platforms, depending on the configuration of the individual process chambers  114 . Slit valves (not shown) in the facets  113  provide access and isolation between the transfer chamber  112  and the process chambers  114 . Correspondingly, the process chambers  114  have openings (not shown) on their surfaces that align with the slit valves. 
     The system  100  includes a gas panel  124  connected to the process chambers  114  through fluid lines (not shown) for delivering process fluids to the process chambers  114  or a vaporizer (not shown). The gas panel  124  connects to a source of the process fluids in the manufacturing facility, and typically delivers the process fluids in a gaseous state to the process chambers  114 . 
     The transfer chamber  112  also has two load lock chambers  118  mounted at facets  115 . Openings (not shown) in the facets  115  provide access and isolation between the load lock chambers  118  and the transfer chamber  112 . Correspondingly, the load lock chambers  118  have openings on their surfaces that align with the openings in facets  115 . The load lock chambers  118  are optionally attached to mini-environment  120 . The load lock chambers  118  and the mini-environment  120  have corresponding openings (not shown) providing access therebetween, while doors  126  for the openings provide isolation. The mini-environment  120  has four pod loaders  122  attached on its front side. Openings (not shown) with corresponding doors  123  provide access and isolation between the mini-environment  114  and the pod loaders  122 . The pod loaders  122  are essentially shelves for supporting pods, or cassettes,  154  containing substrates  156  to be processed in the system  100 . 
     In operation, the pods  154  containing substrates  156  to be processed in the system  100  are placed on the top of the pod loaders  122 . However, when the system  100  is to be diagnosed with a sensor device  200 , then a pod containing only the sensor device, with the switch  216  having been turned on, is placed on one of the pod loaders  122 . Alternatively, if conditions within the system  100  permit, the sensor device  200  may be inserted in a pod containing production substrates, so the sensor device  200  will be transferred through the system  100  with almost no interruption to normal substrate processing. The mini-environment robot  128  removes the sensor device  200  out of the pod  154  and into one of the load lock chambers  118 . During the entire time that the sensor device  200  is within the system  100 , it is transmitting its data to a receiver for further transmission to a controller for storage or processing. Thus, the sensor device  200  begins by transmitting the condition of the pod  154  on the pod loader  122 . When the robot  128  picks up the sensor device  200 , the sensor device  200  can detect any misalignment between the pod  154  and the robot  128 . Afterwards, the sensor device  200  transmits data diagnosing the movement of the robot  128  to the load lock chamber  118 . 
     After the sensor device  200  has been loaded into the load lock chamber  118 , the pressure in the load lock chamber  118  may be reduced to match that in the transfer chamber  112  and simulate actual processing conditions, or the transfer chamber  112  may be pressurized with a purge gas to bring the pressure level of the transfer chamber  112  to that of the load lock chamber  118 . During this time, the sensor device  200  transmits data diagnosing the condition of the load lock chamber  118 . After the load lock chamber  118  opens to the transfer chamber  112 , the substrate handler  116  removes the sensor device  200  from the load lock chamber  118 , and the sensor device  200  can detect any misalignment between the load lock chamber  118  and the substrate handler  116 . If the sensor device  200  is to diagnose the entire system  100 , then the substrate handler  116  moves the sensor device  200  through a representative sample of movements in the transfer chamber  112 , such as in a complete circle as well as to each of the process chambers  114 , while the sensor device  200  detects the conditions during movement, stopping and starting. When the substrate handler  116  moves the sensor device  200  to one of the process chambers  114 , the substrate support structures, such as the lift pins  292  and chuck  294 , receive the sensor device  200  and move the sensor device  200  through a typical set of movements to which a production substrate would be subjected. During this time, the sensor device  200  detects any misalignments between the substrate support structures as well as any irregular movements or improper inclinations. After the sensor device  200  is handled in the process chamber  114 , the substrate handler  116  retrieves the sensor device  200  and moves the sensor device  200  back to one of the load lock chambers  118 , preferably not the same load lock chamber  118  through which the sensor device  200  entered the system  100 , so the other load lock chamber  118  may be diagnosed, too. Additionally, the substrate handler  116  may move the sensor device  200  to other types of chambers or devices, such as a substrate orienter or a cool down chamber. The load lock chamber  118  may transition the pressure to that of the mini-environment  120  or ambient environment, while the sensor device  200  transmits data regarding conditions in the load lock chamber  118 . Afterwards, the substrate handler  128  retrieves the sensor device  200  and moves the sensor device  200  back to a wafer pod  154 . 
     If the controller processes the data from the sensor device  200  while the sensor device  200  is moving through the system  100 , then misalignments, improper inclinations or other irregularities may be determined almost immediately and corrective action may be taken by the operator. For example, if a misalignment is detected between the substrate handler  116  and the lift pins  292  of one of the process chambers  114 , then the operator can adjust the substrate lift mechanism  272  to correct the misalignment. The operator can also cause the substrate lift mechanism  272  and substrate handler  116  to transfer the sensor device  200  back and forth while the operator makes fine adjustments to the substrate lift mechanism  272 . This entire diagnosis and adjustment procedure may be conducted at any time and without opening the system  100  to the external environment. 
     While the foregoing is directed to the preferred embodiment of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims which follow.