Optical system, position detection method and wafer notch positioning detection

Abstract

In an embodiment of the present invention, an optical system may include a light source for providing a light beam. The optical system may include a reflector for receiving and redirecting the light beam. The optical system may include a shutter having an opening to allow the light beam from the reflector to travel through the opening. The optical system may include a light sensor to receive a portion of the light beam after the light beam travels through the opening and convert the portion of the light beam into a signal. The optical system may include a processing device to determine whether a notch of a wafer is in an allowed position based on the signal.

Description

Technical Field

[0001] The embodiments of the present invention relate to an optical system, a position detection method and wafer notch positioning detection. Background Art

[0002] Semiconductor wafers are typically round or circular structures on which semiconductor devices, such as transistors, memory devices, etc., may be fabricated. Small notches may be cut or formed in the semiconductor wafer to facilitate positioning the semiconductor wafer in a repeatable manner during each step of the process flow. For example, the semiconductor wafer may be positioned or oriented relative to the notch to ensure that the semiconductor wafer is in a desired position at each step of the process flow. Summary of the invention

[0003] An optical system according to an embodiment of the present invention includes: a light source for providing a light beam; a reflector for receiving and redirecting the light beam; a light gate having an opening to allow the light beam from the reflector to travel through the opening; a light sensor for: receiving a portion of the light beam after the light beam travels through the opening, and converting the portion of the light beam into a signal; and a processing device for determining whether a notch of a chip is in an allowed position based on the signal.

[0004] A position detection method according to an embodiment of the present invention includes: providing a light beam from a light source toward a reflector; redirecting the light beam from the reflector toward a light gate, wherein the light gate has an opening for allowing the light beam to travel toward a light sensor; receiving a portion of the light beam from the light sensor; converting the portion of the light beam into a signal from the light sensor; and determining, by a processing device based on the signal, whether an offset of a position of a chip notch satisfies a notch offset threshold.

[0005] A position detection device according to an embodiment of the present invention comprises: a reflector for redirecting a light beam; a light gate comprising a partial housing and having one or more openings to allow the light beam from the reflector to travel through one of the one or more openings; a light sensor for converting a portion of the light beam received from the opening of the light gate into a signal; and a processing device for detecting whether a notch of a chip is in an allowed position based on the signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The various aspects of the present disclosure will be best understood by reading the following detailed description in conjunction with the accompanying drawings. It should be noted that, in accordance with standard practice in the industry, various features are not drawn to scale. In fact, the size of various features may be arbitrarily increased or reduced for clarity of discussion.

[0007] Figure 1A and Figure 1Bis a diagram of an exemplary semiconductor processing tool configuration in which the systems, apparatus, and / or methods described herein may be implemented.

[0008] Figures 2A to 2D are drawings associated with exemplary embodiments of a position detection apparatus for performing wafer notch location detection as described herein.

[0009] Figure 3 are diagrams of exemplary components of one or more devices described herein.

[0010] Figure 4 is a flow chart of an exemplary process associated with wafer notch location detection as described herein. DETAILED DESCRIPTION

[0011] The following disclosure provides many different embodiments or examples for implementing the different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. Of course, these are merely examples and are not intended to be limiting. For example, the following description in which a first feature is formed "on" or "on" a second feature may include an embodiment in which the first feature and the second feature are formed to be in direct contact, and may also include an embodiment in which an additional feature may be formed between the first feature and the second feature, thereby making the first feature and the second feature possibly not in direct contact. In addition, the present disclosure may reuse reference numbers and / or letters in various examples. This repetition is for the purpose of brevity and clarity, rather than representing the relationship between the various embodiments and / or configurations discussed in itself.

[0012] Furthermore, for ease of description, spatially relative terms such as "beneath," "below," "lower," "above," "upper," etc. may be used herein to describe the relationship of one element or feature to another (other) element or feature as shown 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 device may be otherwise oriented (rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein should be interpreted accordingly.

[0013] As described above, notches may be cut or formed in a semiconductor wafer to facilitate positioning the semiconductor wafer in a repeatable manner during a process flow. However, during a process flow, positioning of the semiconductor wafer is typically performed first, and then the semiconductor wafer is transferred to one or more process chambers. During this process flow, the position of the semiconductor wafer may shift (causing the notch to shift from an initial position). Such shifts may be caused by, for example, orientation errors of semiconductor processing tools, shaking or vibrations of mechanisms associated with transferring semiconductor wafers between process chambers, lack of friction between the semiconductor wafer and a surface that supports the semiconductor wafer, vibrations of the process chamber, instability of process gas flow, and other examples.

[0014] To determine whether the semiconductor wafer has shifted, in some cases, the position of the semiconductor wafer can be checked based on a notch in the semiconductor wafer and using an image sensor-based technique. According to this technique, an image sensor can capture an image of a portion of the semiconductor wafer. The image sensor can provide information associated with the image to a processing device. The processing device can process and / or analyze the information using one or more techniques (e.g., grayscale analysis, red-green-blue (RGB) splitting, etc.) to determine whether the notch exists and / or whether the notch (and therefore the semiconductor wafer) is in the correct position.

[0015] However, image sensor-based processing is a complex process that involves high-end processing hardware. In addition, image sensor-based processing is susceptible to interference based on lighting conditions in different semiconductor processing tools. Therefore, image sensor-based processing for notch positioning detection is prone to high failure rates and can therefore be applied to a limited range of semiconductor processes. In addition, image sensor-based processing for notch positioning may result in false-positive detection, in which the semiconductor wafer is determined to be in the correct position and / or alignment when the semiconductor wafer is actually out of position and / or misaligned. This may result in reduced semiconductor wafer yield, increased semiconductor wafer waste, etc.

[0016] Some embodiments described herein provide techniques and apparatus for wafer notch positioning detection, which use a light beam (e.g., a laser beam) to detect the position of a semiconductor wafer notch (rather than notch positioning detection based on an image sensor). In some embodiments, the position detection device includes a light source that provides a light beam, a reflector that receives and redirects the light beam, and a light gate having an opening to allow the light beam to travel through the opening. The position detection device may include a light sensor to receive a portion of the light beam after the light beam travels through the opening and convert the portion of the light beam into a signal. The position detection device may also include a processing device for determining, based on the signal, whether the offset of the notch position satisfies the notch offset threshold, whether the notch is in an allowed position, etc. Other details are described below.

[0017] Compared to other notch detection techniques (e.g., the above-mentioned image sensor-based position detection techniques), the use of a light beam to detect the position of a wafer notch is less susceptible to lighting conditions. This allows the position detection device to be used in a wider range of semiconductor manufacturing processes. In addition, this reduces detection errors and reduces false positives (e.g., reduces the likelihood that a notch is erroneously detected as being in the correct position when it is not actually in the correct position). In addition, compared to other notch detection techniques, the position detection device that uses a light beam to detect the notch position is less complex and requires less processing and storage resources.

[0018] Figure 1A and Figure 1B 1 and 150 are diagrams of exemplary semiconductor processing tool configurations 100 and 150, respectively, in which the systems, apparatus, and / or methods described herein may be implemented. Figure 1A and Figure 1B As shown, semiconductor processing tool configuration 100 and semiconductor processing tool configuration 150 may include a set of semiconductor processing chambers 102 and a handler device 104. In some embodiments, semiconductor processing chambers 102 of semiconductor processing tool configurations 100 and 150 may be used to perform one or more processing techniques on a wafer including a semiconductor device. Such processing techniques may include, for example, forming one or more layers of a semiconductor device, removing portions of one or more layers of a semiconductor device, preparing a semiconductor device for one or more processing layers, etc.

[0019] The semiconductor processing chamber 102 may be used to perform processing techniques on wafers including semiconductor devices. A given semiconductor processing chamber 102 may be, for example, a load lock chamber, an orientation chamber, a cooling chamber, an expansion chamber, a pre-cleaning chamber, a degassing chamber, a high bottom coverage chamber, a deposition chamber (e.g., a physical vapor deposition (PVD) chamber, a chemical vapor deposition (CVD) chamber, etc.), a rapid thermal anneal (RTA) chamber, and / or another type of semiconductor processing chamber. In some embodiments, the semiconductor processing tool configuration 100 and / or the semiconductor processing tool configuration 150 may include one or more of the above-described semiconductor processing chambers 102 of a given type.

[0020] The handler 104 includes devices associated with transferring, carrying or moving wafers to and / or between one or more of the aforementioned semiconductor processing chambers 102. For example, the handler 104 may include a robot, a group of robots, etc. Figure 1A The semiconductor processing tool configuration 100 and Figure 1B The arrangement of the semiconductor processing chambers 102 in the semiconductor processing tool configuration 150 is shown for illustrative purposes. One or more semiconductor processing chambers 102 in the semiconductor processing tool configuration 100 or 150 may be arranged in different ways, one or more semiconductor processing chambers 102 may be spaced apart from other semiconductor processing chambers 102 (e.g., the semiconductor processing chambers 102 may be spaced apart, and the handler 110 may be a robot that transports wafers to and / or from the spaced apart semiconductor processing chambers 102), etc. In addition, Figure 1A and Figure 1B The semiconductor processing chamber 102 included in the illustrated semiconductor processing tool configurations 100 and 150 may be used in conjunction with other semiconductor processing tools and / or chambers to further fabricate and / or process semiconductor devices, such as etch tools, photoresist tools.

[0021] like Figure 1A and Figure 1B As further shown, the semiconductor processing tool arrangement 100 and the semiconductor processing tool arrangement 150 may also include an optical system associated with determining information related to the wafer position. For example, the optical system (referred to herein as the position detection device 200) may determine whether the offset of the notch position satisfies the notch offset threshold, whether the notch is in an allowed position, etc., as described in further detail below. In some embodiments, Figure 1A and Figure 1BAs shown, the position detection device 200 may be disposed on, in, or near one of the semiconductor processing chambers 102. For example, the position detection device 200 may be disposed on, in, or near a cooling chamber of the semiconductor processing tool arrangement 100 or the semiconductor processing tool arrangement 150.

[0022] As mentioned above, Figure 1A and Figure 1B These are examples only. Other examples may differ from those described in Figure 1A and Figure 1B Described example.

[0023] Figures 2A to 2D is a diagram associated with an exemplary embodiment of a position detection apparatus 200 for performing wafer notch location detection as described herein. Figure 2A As shown, the position detection device 200 may include a light source 202, a reflector 204, a shutter 206 including an opening 208, a light sensor 210, and a processing device 212. In some embodiments, as described above, the position detection device 200 may be able to determine whether the offset of the position of the notch 252 of the wafer 250 meets the notch offset threshold, whether the notch 252 is in an allowed position, etc.

[0024] The components of the position detection device 200 are described below, followed by a description of an exemplary operation of the position detection device 200 .

[0025] The light source 202 includes a component that provides a light beam 220. For example, the light source 202 may include an emitter, such as a laser, a light emitting diode (LED), etc. In some embodiments, Figure 2A As shown, the light source 202 may be arranged to provide a light beam 220 toward the reflector 204 .

[0026] The reflector 204 includes a component that redirects the light beam 220 (e.g., toward the shutter 206). In some embodiments, the light source 202 includes one or more reflective surfaces 204s to redirect the light beam 220. As a specific example, Figure 2BAs shown, the position detection device 200 may include a first surface 204s1 (e.g., a first reflector) and a second surface 204s2 (e.g., a second reflector), the surfaces being at angles α1 and α2 relative to an axis (e.g., a horizontal axis), respectively. As shown, the reflector 204 may be arranged to redirect the light beam 220 by reflecting the light beam 220 from the first surface 204s1 toward the second surface 204s2, and then reflecting the light beam 220 from the second surface 204s2 toward the opening 208 of the optical gate 206. In some embodiments, the angles α1 and α2 are the same angle. In some embodiments, the angles α1 and α2 are different angles. Whether the angles α1 and α2 are the same angle or different angles may depend on the arrangement of the components of the position detection device 200. It should be noted that although Figure 2A and Figure 2B The reflector 204 shown includes two reflective surfaces 204s, but in other embodiments, the reflector 204 may include a different number of reflective surfaces 204s (e.g., one reflective surface 204s, three or more reflective surfaces 204s, etc.) depending on the arrangement of the components of the position detection device 200.

[0027] return Figure 2A , the shutter 206 includes a device that allows the light beam 220 to travel toward the light sensor 210. For example, the shutter 206 can include an opening 208 that allows the light beam 220 to propagate toward the light sensor 210. In some embodiments, the opening 208 can be used to filter out divergent light from the light beam 220.

[0028] Figure 2C 2 is a diagram showing a plan view of an exemplary top surface of the shutter 206. Figure 2C As shown, the shutter 206 may have a length a and a width b. In some embodiments, the length a and the width b may be about tens of millimeters (mm). For example, in some embodiments, the length a may be about 24 mm, and the width b may be about 40 mm. Figure 2C As further shown, the opening 208 may have a length c and a width d, wherein the length c is less than the length a, and the width d is less than the width b. In some embodiments, the length c and the width d may be approximately other millimeters or micrometers. It should be noted that although Figure 2A and Figure 2C The shutter 206 shown in FIG. 2 includes one opening 208, but in other embodiments, the shutter 206 may include two or more openings 208. In some embodiments, the size (e.g., length c) of the opening 208 may be greater than or equal to the size of the notch 252. For example, the length c may be greater than or equal to the width of the widest portion of the notch 252. In some embodiments, the size of the opening 208 corresponds to a range of allowable positions of the notch 252, as described below.

[0029] return Figure 2A In some embodiments, the shutter 206 can include a partial housing 206 e. The partial housing 206 e can be used to prevent the opening 208 from allowing unwanted light (eg, ambient light) to travel toward the light sensor 210.

[0030] The light sensor 210 includes a component that converts a portion 220p of the light beam 220 into a signal 225 (e.g., an electrical signal). For example, the light sensor 210 may include one or more photodiodes (e.g., a photodiode array) capable of converting light incident thereon into an electric current. The portion 220p of the light beam 220 is the portion of the light beam 220 that reaches (e.g., is incident on) the light sensor 210 after the light beam 220 travels through the opening 208. The portion 220p of the light beam 220 is defined herein as including the entire light beam 220, a portion of the light beam 220 that is less than the entire light beam 220, or no light beam 220. In some embodiments, the light sensor 210 converts the portion 220p of the light beam 220 into the signal 225 such that a characteristic value (e.g., current, voltage, etc.) of the signal 225 corresponds to the intensity of the portion 220p of the light beam 220. Therefore, in some embodiments, the characteristic of the signal 225 may indicate the intensity of the portion 220p of the light beam 220. In some embodiments, as Figure 2A As shown, light sensor 210 may be arranged to receive portion 220 p of light beam 220 after light beam 220 travels through opening 208 .

[0031] The processing device 212 includes a component that determines position information associated with the notch 252 of the wafer 250 based on the signal 225. For example, the processing device 212 may be able to determine whether the notch 252 of the wafer 250 is in an allowed position based on the signal 225. As another example, the processing device 212 may be able to determine whether an offset in the position of the notch 252 (e.g., a deviation from the position of the notch 252 after the wafer 250 is oriented) satisfies a notch offset threshold based on the signal 225.

[0032] In some embodiments, the processing device 212 may determine the position information based on the signal 225. For example, the characteristic value (e.g., voltage, current) of the signal 225 may depend on the intensity of the portion 220p of the light beam 220 incident on the light sensor 210, as described above. Therefore, a relatively large portion 220p of the light beam 220 causes the characteristic value of the signal 225 to be large, while a relatively small portion 220p of the light beam 220 causes the characteristic value of the signal 225 to be relatively small. Here, the processing device 212 may determine whether the characteristic value (e.g., a voltage level corresponding to the intensity of the portion 220p of the light beam 220) satisfies a threshold. If the value is greater than or equal to the threshold (indicating that the notch 252 is substantially above the opening 208), the processing device 212 may determine that the notch 252 is in the allowed position and / or the offset of the position of the notch 252 satisfies the notch offset threshold. Conversely, if the value is less than the threshold (indicating that notch 252 is not substantially over opening 208 ), processing device 212 may determine that notch 252 is not in an allowed position and / or the offset in the position of notch 252 does not satisfy the notch offset threshold.

[0033] Figure 2D Included are exemplary drawings that illustrate the present concepts. Figure 2D In the left portion of FIG. 2 , the notch 252 is substantially above the opening 208 (e.g., the length of the notch 252 is completely within the length c of the opening 208). This means that a relatively large portion 220p of the light beam 220 travels through the notch 252. Therefore, the intensity of the portion 220p is relatively high at the light sensor 210 (e.g., Figure 2D ). Thus, the characteristic value of signal 225 may be greater than or equal to the threshold, and thus processing device 212 may determine that notch 252 is in the permitted position and / or the offset of the position of notch 252 satisfies the notch offset threshold. Figure 2D In the right portion of FIG. 2 , the notch 252 is not substantially above the opening 208 (e.g., the length of the notch 252 is mostly outside the length c of the opening 208). This means that a relatively small portion 220p of the light beam 220 travels through the notch 252. Therefore, the intensity of the portion 220p is relatively low at the light sensor 210 (e.g., Figure 2D ). Therefore, the characteristic value of the signal 225 may be less than the threshold, and thus the processing device 212 may determine that the notch 252 is not in the allowed position and / or the offset of the position of the notch 252 does not satisfy the notch offset threshold. It should be noted that in the present example, the size of the opening 208 defines the allowed displacement of the notch 252 and / or the notch offset threshold (e.g., from the initial position).

[0034] In some embodiments, the processing device 212 can provide an indication of whether the notch 252 is in an allowed position and / or whether the offset of the position of the notch 252 satisfies a notch offset threshold. For example, when the processing device 212 determines that the notch 252 is not in an allowed position and / or determines that the offset of the position of the notch 252 does not satisfy the notch offset threshold, the processing device 212 can trigger an alarm.

[0035] Additionally or alternatively, the processing device 212 may cause an action to be performed based on the result of whether the notch 252 is in an allowed position and / or whether the offset of the position of the notch 252 satisfies a notch offset threshold. For example, if the processing device 212 determines that the notch 252 is not in an allowed position or the offset of the position of the notch 252 does not satisfy the notch offset threshold, the processing device 212 may cause an action associated with attempting to save the wafer 250 to be performed. Such an action may include, for example, causing the wafer 250 to be transferred for reconditioning or repair, causing photolithography alignment marks on the wafer 250 to be adjusted based on the offset of the notch 252, etc. As another example, if the processing device 212 determines that the notch 252 is in an allowed position or the offset of the position of the notch 252 satisfies the notch offset threshold, the processing device 212 may cause the wafer 250 to advance to the next step in the process flow (e.g., the processing device 212 may cause the wafer 250 to advance to the next semiconductor processing tool for further processing).

[0036] In operation, the light source 202 provides a light beam 220 toward the reflector 204. Next, the reflector 204 receives the light beam 220 and redirects the light beam 220 toward the shutter 206. The shutter 206 has an opening 208 that allows the light beam 220 from the reflector 204 to pass through the opening 208 toward the light sensor 210. After the light beam 220 passes through the opening 208 and the notch 252, the light sensor 210 receives a portion 220p of the light beam 220. The light sensor 210 converts the portion 220p of the light beam 220 into a signal 225 and provides the signal 225 to the processing device 212. The processing device 212 then determines, based on the signal 225, whether the notch 252 of the wafer 250 is in an allowed position and / or whether the offset of the position of the notch 252 meets the notch offset threshold. In some embodiments, as described above, the processing device 212 provides an indication associated with the determination result, triggers an alarm based on the determination result, and / or causes an action to be performed based on the determination result.

[0037] As mentioned above, Figures 2A to 2D These are examples only. Other examples may differ from those described in Figures 2A to 2D Described example.

[0038] Figure 3is a diagram of exemplary components of apparatus 300. In some embodiments, semiconductor processing chamber 102, handler apparatus 110, light source 202, light sensor 210, and / or processing apparatus 212 may include one or more apparatus 300 and / or one or more components of apparatus 300.

[0039] like Figure 3 As shown, device 300 may include a bus 310 , a processor 320 , a memory 330 , a storage component 340 , an input component 350 , an output component 360 , and a communication component 370 .

[0040] The bus 310 includes components that enable wired and / or wireless communications between components of the device 300. The processor 320 includes 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. The processor 320 is implemented in hardware, firmware, or a combination of hardware and software. In some embodiments, the processor 320 includes one or more processors that can be programmed to perform functions. The memory 330 includes a random access memory, a read-only memory, and / or another type of memory (e.g., flash memory, magnetic memory, and / or optical memory).

[0041] The storage component 340 stores information and / or software related to the operation of the device 300. For example, the storage component 340 may include a hard disk drive, a magnetic disk drive, an optical disk drive, a solid state disk drive, a compact disk, a digital versatile disk, and / or another type of non-transitory computer-readable medium. The input component 350 enables the device 300 to receive input, such as user input and / or sensory input. For example, the input component 350 may 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, an actuator, etc. The output component 360 enables the device 300 to provide output, such as via a display, a speaker, and / or one or more light-emitting diodes. The communication component 370 enables the device 300 to communicate with other devices, such as via a wired connection and / or a wireless connection. For example, the communication component 370 may include a receiver, a transmitter, a transceiver, a modem, a network interface card, an antenna, etc.

[0042] The device 300 may implement one or more processes described herein. For example, a non-transitory computer-readable medium (e.g., memory 330 and / or storage component 340) may store a set of instructions (e.g., one or more instructions, codes, software codes, program codes, etc.) for execution by the processor 320. The processor 320 may execute the set of instructions to implement one or more processes described herein. In some embodiments, the execution of the set of instructions by one or more processors 320 causes one or more processors 320 and / or the device 300 to implement one or more processes described herein. In some embodiments, a hard-wired circuit system may be used instead of an instruction or in combination with an instruction to implement one or more processes described herein. Therefore, the embodiments described herein are not limited to any specific combination of hardware circuit systems and software.

[0043] supply Figure 3 The number and arrangement of components shown in FIG. 3 are provided as examples. The device 300 may include Figure 3 The components shown may include additional components, fewer components, different components, or components arranged in a different manner. Additionally or alternatively, one or more components of the device 300 may implement one or more functions described as being implemented by another group of components of the device 300.

[0044] Figure 4 is a flow chart of an exemplary process 400 associated with wafer notch positioning detection as described herein. In some embodiments, Figure 4 One or more process blocks of may be performed by a position detection device (eg, position detection device 200). Additionally or alternatively, Figure 4 One or more process blocks may be performed by one or more components of the device 300 (eg, processor 320, memory 330, storage component 340, input component 350, output component 360, communication component 370, etc.).

[0045] like Figure 4 As shown, process 400 may include providing a light beam toward a reflector (block 410). For example, as described above, light source 202 of position detection device 200 may provide light beam 220 toward reflector 204 of position detection device 200.

[0046] like Figure 4As further shown, process 400 may include redirecting the light beam toward a light gate having an opening that allows the light beam to travel toward the light sensor (block 420). For example, reflector 204 of position detection device 200 may redirect light beam 220 toward light gate 206 of position detection device 200, light gate 206 having an opening 208 that allows light beam 220 to travel toward light sensor 210 of position detection device 200, as described above.

[0047] like Figure 4 As further shown, process 400 may include receiving a portion of the light beam (block 430). For example, light sensor 210 of position detection device 200 may receive portion 220p of light beam 220, as described above.

[0048] like Figure 4 As further shown, process 400 may include converting the portion of the light beam into a signal (block 440). For example, light sensor 210 of position detection device 200 may convert portion 220p of light beam 220 into signal 225, as described above.

[0049] like Figure 4 As further shown, the process 400 may include determining whether the offset of the position of the wafer notch meets the notch offset threshold based on the signal (block 450). For example, the processing device 212 of the position detection device 200 may determine whether the offset of the position of the wafer notch 252 of the wafer 250 (e.g., semiconductor wafer) meets the notch offset threshold based on the signal 225, as described above.

[0050] Process 400 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in combination with one or more other processes described elsewhere herein.

[0051] In some implementations, process 400 includes filtering divergent light from light beam 220 through opening 208 of light gate 206 , which is associated with allowing light beam 220 to travel toward light sensor 210 .

[0052] In some implementations, redirecting the light beam 220 toward the shutter 206 includes reflecting the light beam 220 toward the second surface 204s2 of the reflector 204 through the first surface 204s1 of the reflector 204 , and reflecting the light beam 220 toward the opening 208 through the second surface 204s2 of the reflector 204 .

[0053] In some embodiments, a characteristic value of the signal 225 depends on the intensity of the portion 220 p of the light beam 220 .

[0054] In some embodiments, process 400 includes providing (eg, by processing device 212 ) an indication of a result of determining whether an offset in the location of wafer notch 252 satisfies a notch offset threshold.

[0055] In some embodiments, process 400 includes triggering (eg, by processing device 212 ) an alarm when determining whether the offset of the position of wafer notch 252 satisfies the notch offset threshold results in the offset of the position of wafer notch 252 not satisfying the notch offset threshold.

[0056] In some embodiments, the shutter 206 includes a partial housing 206e.

[0057] In some embodiments, the size of the opening 208 is greater than or equal to the size of the wafer notch 252. In some embodiments, the size of the opening 208 corresponds to a range of allowed positions of the wafer notch 252.

[0058] although Figure 4 Example blocks of process 400 are shown, but in some embodiments, process 400 may include Figure 4 The blocks depicted in the process 400 may include additional blocks, fewer blocks, different blocks, or blocks arranged in a different manner than those depicted in the process 400. Additionally or alternatively, two or more blocks of the process 400 may be performed in parallel.

[0059] In this way, wafer notch positioning detection can be implemented by a position detection device using a light beam. For example, the position detection device 200 may include a light source 202 that provides a light beam 220, a reflector 204 that receives and redirects the light beam 220, and a shutter 206 having an opening 208 to allow the light beam 220 to travel through the opening 208. The position detection device 200 may also include a light sensor 210 to receive a portion 220p of the light beam 220 after the light beam 220 travels through the opening 208, and convert the portion 220p of the light beam 220 into a signal 225. The position detection device 200 may also include a processing device 212 for determining whether the offset of the position of the notch 252 satisfies a notch offset threshold, whether the notch 252 is in an allowed position, etc. based on the signal 225.

[0060] It should be noted that the operation of the position detection device 200 is less susceptible to lighting conditions than other notch detection techniques, such as the above-mentioned image sensor-based position detection techniques. This allows the position detection device 200 to be used in a wider range of semiconductor manufacturing processes. In addition, the position detection device 200 reduces detection errors and reduces false positives (e.g., reduces the likelihood that a notch is erroneously detected as being in the correct position when it is not actually in the correct position). In addition, the position detection device 200 is less complex and requires fewer processing and storage resources than other notch detection techniques.

[0061] As described in more detail above, some embodiments described herein provide optical systems, methods, and position detection apparatus associated with performing wafer notch location detection.

[0062] In some embodiments, an optical system includes: a light source for providing a light beam; a reflector for receiving and redirecting the light beam; and a shutter having an opening to allow the light beam from the reflector to travel through the opening. In some embodiments, the optical system includes a light sensor to receive a portion of the light beam after the light beam travels through the opening and convert the portion of the light beam into a signal. In some embodiments, the optical system includes a processing device to determine whether a notch of a wafer is in an allowed position based on the signal.

[0063] In some embodiments, the shutter comprises a portion of the housing.

[0064] In some embodiments, the opening is used to filter out divergent light from the light beam.

[0065] In some embodiments, the size of the opening is greater than or equal to the size of the recess.

[0066] In some implementations, the reflector includes one or more angled surfaces associated with redirecting the light beam toward the shutter.

[0067] In some embodiments, the light sensor is configured to convert the portion of the light beam into the signal such that a characteristic value of the signal corresponds to an intensity of the portion of the light beam.

[0068] In some embodiments, the processing device is further configured to provide an indication of whether the notch of the wafer is in the allowed position.

[0069] In some embodiments, the processing device is further configured to trigger an alarm when the processing device determines that the notch of the wafer is not in the allowed position.

[0070] In some embodiments, the method includes providing a light beam by a light source toward a reflector. In some embodiments, the method includes redirecting the light beam by the reflector toward a light gate having an opening that allows the light beam to travel toward a light sensor. In some embodiments, the method includes receiving a portion of the light beam by the light sensor, and converting the portion of the light beam by the light sensor into a signal. In some embodiments, the method includes determining, by a processing device based on the signal, whether an offset in a position of a wafer notch satisfies a notch offset threshold.

[0071] In some implementations, the method further includes filtering divergent light from the light beam through the opening of the light gate, which is associated with allowing the light beam to travel toward the light sensor.

[0072] In some implementations, redirecting the light beam toward the shutter includes: reflecting the light beam by a first surface of the reflector toward a second surface of the reflector; and reflecting the light beam by the second surface of the reflector toward the opening.

[0073] In some embodiments, a characteristic value of the signal depends on an intensity of the portion of the light beam.

[0074] In some implementations, the method further includes providing an indication of a result of determining whether the offset of the position of the wafer notch satisfies the notch offset threshold.

[0075] In some embodiments, the method further includes triggering an alarm when a result of determining whether the offset of the position of the wafer notch satisfies the notch offset threshold is that the offset of the position of the wafer notch does not satisfy the notch offset threshold.

[0076] In some embodiments, the position detection device includes a reflector for redirecting the light beam. In some embodiments, the position detection device includes a shutter, the shutter including a partial housing and having one or more openings to allow the light beam from the reflector to travel through one of the one or more openings. In some embodiments, the position detection device includes a light sensor for converting a portion of the light beam received from the opening of the shutter into a signal. In some embodiments, the position detection device includes a processing device for detecting whether the notch of the wafer is in an allowed position based on the signal.

[0077] In some embodiments, the position detection device further comprises a light source, and the light source is configured to provide the light beam toward the reflector.

[0078] In some embodiments, the size of the opening corresponds to a range of allowed positions of the notch.

[0079] In some implementations, the reflector includes at least one angled surface associated with redirecting the light beam toward the shutter.

[0080] In some embodiments, a characteristic value of the signal depends on an intensity of the portion of the light beam.

[0081] In some embodiments, the processing device is further configured to cause an action to be performed based on a result of whether the notch of the wafer is in an allowed position.

[0082] The features of several embodiments are summarized above so that those skilled in the art can better understand the various aspects of the present disclosure. Those skilled in the art will appreciate that they can easily use the present disclosure as a basis for designing or modifying other processes and structures to implement the same purposes and / or achieve the same advantages as the embodiments described herein. Those skilled in the art will also recognize that these equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they can make various changes, substitutions, and modifications thereto without departing from the spirit and scope of the present disclosure.

Claims

1. An optical system, comprising: a light source for providing a light beam; a reflector comprising a first surface for receiving the light beam and redirecting the light beam to a second surface of the reflector; a shutter having an opening to allow the light beam reflected from the second surface of the reflector to travel through the opening; Light sensors for: receiving a portion of the light beam after the light beam travels through the opening, and converting the portion of the light beam into a signal; as well as A processing device is used to determine whether the notch of the wafer is in an allowed position based on the signal.

2. The optical system of claim 1, wherein the shutter comprises a portion of a housing.

3. The optical system of claim 1, wherein the opening is used to filter out divergent light from the light beam. The optical system of claim 1 , wherein a size of the opening is greater than or equal to a size of the recess.

5. The optical system of claim 1, wherein the reflector comprises one or more angled surfaces associated with redirecting the light beam toward the shutter.

6. The optical system of claim 1, wherein the light sensor is configured to convert the portion of the light beam into the signal such that a characteristic value of the signal corresponds to an intensity of the portion of the light beam.

7. The optical system of claim 1, wherein the processing device is further configured to provide an indication of whether the notch of the wafer is in the allowed position.

8. The optical system of claim 1, wherein the processing device is further configured to trigger an alarm when the processing device determines that the notch of the wafer is not in the allowed position.

9. A position detection method, comprising: A light beam is provided by a light source toward a reflector; redirecting the light beam from a first surface of the reflector toward a second surface of the reflector; reflecting the light beam by the second surface of the reflector toward an opening of a light shutter, the opening of the light shutter allowing the light beam to travel toward a light sensor; receiving, by the light sensor, a portion of the light beam; converting the portion of the light beam into a signal by the light sensor; as well as The processing device determines whether the offset of the position of the wafer notch meets the notch offset threshold based on the signal.

10. The method of claim 9, further comprising filtering divergent light from the light beam through the opening of the shutter, which is associated with allowing the light beam to travel toward the light sensor.

11. The method of claim 9, wherein a characteristic value of the signal depends on an intensity of the portion of the light beam.

12. The method of claim 9, further comprising providing an indication of a result of determining whether the offset of the position of the wafer notch satisfies the notch offset threshold.

13. The method according to claim 9, further comprising triggering an alarm when the result of determining whether the offset of the position of the wafer notch satisfies the notch offset threshold is that the offset of the position of the wafer notch does not satisfy the notch offset threshold.

14. A position detection device, comprising: a reflector comprising a first surface for redirecting a light beam to a second surface of the reflector; a shutter comprising a portion of the housing and having one or more openings to permit the light beam reflected from the second surface of the reflector to travel through one of the one or more openings; a light sensor for converting a portion of the light beam received from the opening of the light shutter into a signal; as well as A processing device is used to detect whether the notch of the wafer is in an allowed position based on the signal.

15. The position detection device according to claim 14, further comprising a light source for providing the light beam toward the reflector.

16. The position detection device of claim 14, wherein the size of the opening corresponds to a range of allowed positions of the recess.

17. The position detection device of claim 14, wherein the reflector includes at least one angled surface associated with redirecting the light beam toward the shutter.

18. A position detection device according to claim 14, wherein a characteristic value of the signal depends on the intensity of the portion of the light beam.

19. The position detection device according to claim 14, wherein the processing device is further configured to cause an action to be performed based on a result of whether the notch of the wafer is in an allowed position.

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