Filter circuit and wafer detection system
By filtering out the jitter signal of the wafer detection equipment through the parallel connection of the filter module, the problem of low wafer imaging quality is solved, higher quality imaging effect is achieved and circuit cost is reduced.
Patent Information
- Application Number
- CN202422974419.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-03
- Publication Date
- 2025-10-21
- Estimated Expiration
- 2034-12-03
AI Technical Summary
During the wafer manufacturing process, there are jitter signals in the signals output by the detection equipment, which affects the imaging quality.
A first filtering module and a second filtering module connected in parallel are used to filter out signals lower than or equal to the first frequency and higher than or equal to the second frequency respectively. The second frequency is greater than the first frequency, and the jitter signal is filtered out.
The imaging quality of the display device is improved, the circuit cost is reduced, and the output signals of different detection devices are adapted.
Smart Images
Figure CN223462998U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of electronic circuits, and particularly relates to a filter circuit and a wafer detection system. BACKGROUND
[0002] In a wafer manufacturing process, a wafer often needs to be detected by multiple different detection devices such as an electron beam defect detection device, a size measurement device, or an electron beam defect review device, and output signals, and then an image is displayed by a display device so that a technician can observe the image to determine possible problems in the wafer manufacturing process.
[0003] However, there may be jitter signals in the output signals of the detection devices, affecting imaging. The prior art often filters jitter signals by connecting the output signals to a reference voltage terminal, but the above-mentioned method cannot completely filter jitter signals, so that the imaging quality based on the output signals is still low. CONTENT OF THE INVENTION
[0004] The application embodiment provides a filter circuit and a wafer detection system, which can filter jitter signals existing in a wafer detection device and improve filtering effect.
[0005] In a first aspect, the application embodiment provides a filter circuit applied to a detection device for wafer manufacturing, and the circuit comprises:
[0006] A first filter module, a first end of the first filter module being electrically connected to an output signal terminal of the detection device, and a second end of the first filter module being electrically connected to a display device, so as to filter signals lower than or equal to a first frequency.
[0007] A second filter module, the second filter module being connected in parallel with the first filter module between the output signal terminal and the display device, so as to filter signals higher than or equal to a second frequency, the second frequency being greater than the first frequency.
[0008] In a second aspect, the application embodiment provides a wafer detection system, which comprises:
[0009] The detection device, the display device, and the filter circuit as shown in the first aspect.
[0010] The filter circuit and the wafer detection system provided by the application embodiment can filter jitter signals based on the first filter module and the second filter module connected in parallel between the output signal terminal of the detection device and the display device, solve the influence of jitter signals on the output signals of the detection device in the prior art, and improve the imaging quality of the image displayed by the display device. BRIEF DESCRIPTION OF DRAWINGS
[0011] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly introduced. Those drawings can help the ordinary skilled in the art to obtain other drawings without any creative effort.
[0012] Figure 1 A schematic diagram of a wafer detection system provided for some embodiments of the present application.
[0013] Figure 2 A schematic diagram of a filter circuit provided for some embodiments of the present application.
[0014] Figure 3 Another schematic diagram of a filter circuit provided for some embodiments of the present application.
[0015] Figure 4 Still another schematic diagram of a filter circuit provided for some embodiments of the present application. DETAILED DESCRIPTION
[0016] The features and exemplary embodiments of various aspects of the present application will be described in detail below with reference to the drawings. In order to make the purpose, technical solutions and advantages of the present application more clear, the present application will be further described in detail below with reference to the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, but not to limit the present application. The present application can be implemented without some of the specific details by those skilled in the art. The following description of the embodiments is only intended to provide a better understanding of the present application by showing examples of the present application.
[0017] It should be noted that, in this document, the relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without more limitations, the elements defined by the statement "include" do not exclude the presence of other identical elements in the process, method, article or device including the elements.
[0018] Currently, in the wafer manufacturing process, different detection devices are needed, such as a defect review scanning electron microscope (DRSEM), a critical dimension scanning electron microscope (CDSEM), or an e-beam inspection (EBI), and the output signals of the above devices are used to display images by the display device to detect the wafer. However, the output signals of the above devices often have jitter signals, such as 150Hz jitter signals, which affect the imaging quality and further affect the observation of the wafer.
[0019] Therefore, based on the above, the embodiments of the present application provide a filtering circuit and a wafer detection system, which can solve the above problems.
[0020] As shown in Figure 1 , the embodiments of the present application provide a wafer detection system, which includes:
[0021] The detection device 101, the display device 102, and the filtering circuit 103.
[0022] The above detection device can be a DRSEM, a CDSEM, or an EBI, and the above detection device is used to detect different parameters in the wafer manufacturing process, such as the DRSEM and the EBI used to detect the parameters of the electron beam, and the CDSEM can be used to detect the size of the wafer. The display device can be used to display the images based on the output signals output by the above different devices, such as the beam output signals.
[0023] The filtering circuit can be arranged between the output signal end of the above detection device and the display device, and the filtering circuit is used to filter out the jitter signals in the output signals output by the output signal end.
[0024] The embodiments of the present application can filter out the jitter signals in the output signals output by the detection device through the filtering circuit by arranging the above wafer detection system, and improve the quality of the images displayed by the display device.
[0025] Next, the structure of the above filtering circuit will be described in detail.
[0026] In some embodiments, as shown in Figure 2 , the embodiments of the present application provide a filtering circuit applied to a detection device in wafer manufacturing, and the circuit includes:
[0027] The first filter module 201 is electrically connected to the output signal end of the detection device, and the second end of the first filter module 201 is electrically connected to the display device, so as to filter out signals lower than or equal to the first frequency. The second filter module 202 is connected in parallel with the first filter module 201 between the output signal end and the display device, so as to filter out signals higher than or equal to the second frequency, and the second frequency is greater than the first frequency.
[0028] As shown in Figure 2 The embodiment of the present application provides a filter circuit, and the filter circuit comprises a first filter module 201 and a second filter module 202 connected in parallel between an output signal end of a detection device and a display device. The first filter module 201 can be used to filter out signals lower than or equal to the first frequency, and the second filter module 202 can be used to filter out signals higher than or equal to the second frequency. Here, the first filter module 201 can comprise any one of a capacitor, a capacitor-resistor filter module or a capacitor-inductor filter module, and the second filter module 202 can also comprise any one of a capacitor, a capacitor-resistor filter module or a capacitor-inductor filter module.
[0029] In some embodiments, when the detection device comprises a DRSEM, a CDSEM or an EBI, the filter module can adapt to the output signals of different detection devices by setting the parameters of the devices in the filter module, thereby improving the universality of the filter module.
[0030] The embodiment of the present application can filter out the jitter signals in the output signals of the detection device in the wafer manufacturing process by setting the filter circuit of the first filter module 201 and the second filter module 202, thereby solving the influence of the jitter signals on the output signals of the detection device in the prior art and improving the imaging quality of the imaging displayed by the display device.
[0031] In some embodiments, the first filter module 201 can comprise at least one first filter sub-module, and the at least one first filter sub-module can be connected in series between the output signal end and the display device. For example, the first filter sub-module can comprise a capacitor-resistor filter module, and at least one capacitor-resistor filter module can be connected in series between the output signal end and the display device.
[0032] By connecting the at least one first filter sub-module in series between the output signal end and the display device, the jitter signals can be further filtered out, and the filtering effect of filtering out signals less than or equal to the first frequency can be improved.
[0033] In some embodiments, as shown in Figure 3 The first filter sub-module can comprise:
[0034] The first filtering unit 301 has a first end electrically connected to the output signal end; the second filtering unit 302 has a first end electrically connected to the second end of the first filtering unit 301 and the reference voltage end GND.
[0035] like Figure 3 As shown, Figure 3 This is a schematic diagram of an exemplary filtering circuit. The above-mentioned first filtering submodule can be a capacitor-resistor filtering module. The above-mentioned first filtering module 201 can include a first filtering unit 301 and a second filtering unit 302. Here, the first filtering unit 301 can include a capacitor or a resistor, and the second filtering unit 302 can include a capacitor or a resistor. When the first filtering unit 301 is a resistor, the second filtering unit 302 is a capacitor. When the first filtering unit 301 is a capacitor, the second filtering unit 302 is a resistor.
[0036] In some embodiments, the first filtering submodule may be a capacitor-inductor filtering module. Here, the first filtering unit 301 may include an inductor, and the second filtering unit 302 may include a capacitor.
[0037] In the embodiment of the present application, the first filtering submodule includes a first filtering unit 301 and a second filtering unit 302 , and signals lower than or equal to the first frequency are filtered out by only two filtering units, thereby reducing circuit costs while achieving filtering.
[0038] In some embodiments, the second filtering module 202 may include at least one second filtering submodule, wherein the at least one second filtering submodule is connected in series between the output signal terminal and the display device. For example, the second filtering submodule may include a capacitor-inductor filtering module, wherein the at least one capacitor-inductor filtering module is connected in series between the output signal terminal and the display device.
[0039] By providing at least one second filtering submodule connected in series between the output signal terminal and the display device, the jitter signal can be further filtered out, thereby improving the filtering effect of filtering out signals less than or equal to the second filter signal.
[0040] In some embodiments, as Figure 3 The second filtering submodule may include:
[0041] The third filtering unit 303 has a first end electrically connected to the output signal end; the fourth filtering unit 304 has a first end electrically connected to the second end of the third filtering unit 303 and the reference voltage end GND.
[0042] Here, the second filtering sub-module can include a third filtering unit 303 and a fourth filtering unit 304, the third filtering unit 303 can include a resistor, a capacitor or an inductor, and the fourth filtering unit 304 can include a resistor, a capacitor or an inductor. In the case where the third filtering unit 303 includes a resistor, the fourth filtering unit 304 can include a capacitor; in the case where the third filtering unit 303 includes a capacitor, the fourth filtering unit 304 can include an inductor; and in the case where the third filtering unit 303 includes an inductor, the fourth filtering unit 304 can include a capacitor.
[0043] In some examples, in the case where the first filtering unit 301 includes a resistor and the second filtering unit 302 includes a capacitor, the third filtering unit 303 can include a capacitor and the fourth filtering unit 304 can include an inductor, or in the case where the first filtering unit 301 includes a resistor and the second filtering unit 302 includes a capacitor, the third filtering unit 303 can include an inductor and the fourth filtering unit 304 can include a capacitor.
[0044] In some examples, in the case where the first filtering unit 301 includes a capacitor and the second filtering unit 302 includes a resistor, the third filtering unit 303 can include a capacitor and the fourth filtering unit 304 can include an inductor, or in the case where the first filtering unit 301 includes a capacitor and the second filtering unit 302 includes a resistor, the third filtering unit 303 can include an inductor and the fourth filtering unit 304 can include a capacitor.
[0045] In some examples, in the case where the first filtering unit 301 includes an inductor and the second filtering unit 302 includes a capacitor, the third filtering unit 303 can include a capacitor and the fourth filtering unit 304 can include an inductor.
[0046] The embodiment of the present application sets the second filtering sub-module to include the third filtering unit 303 and the fourth filtering unit 304, filters out signals lower than or equal to the second frequency by only two filtering units, and can reduce the circuit cost while achieving filtering.
[0047] In some embodiments, as shown in Figure 4 , Figure 4 is a schematic diagram of an exemplary filtering circuit, as shown in Figure 4 , the first filtering unit 301 can include a resistor R1, and the second filtering unit 302 can include a first capacitor C1. The third filtering unit 303 can include an inductor L, and the fourth filtering unit 304 can include a second capacitor C2.
[0048] In some examples, in the case where the frequency of the dithering signal is determined, for example, in the case where the frequency of the dithering signal is 150 Hz, the parameters of R1 and C1 can be determined based on the following formula:
[0049]
[0050] Where f is the frequency of the jitter signal, R is the resistance of the resistor, and C is the size of the capacitor.
[0051] In some examples, when the frequency of the dithering signal is determined, the parameters of R1 and C1 can be determined based on the following formula:
[0052]
[0053] Wherein, f is the frequency of the jitter signal, L is the size of the inductor, and C is the size of the capacitor.
[0054] In the embodiment of the present application, by setting a filtering circuit in which the first filtering unit 301 includes R1, the second filtering unit 302 includes C1, the third filtering unit 303 includes L, and the fourth filtering unit 304 includes C2, it is possible to filter out signals lower than or equal to the first frequency and signals higher than or equal to the second frequency based on the above filtering circuit, thereby reducing circuit costs while achieving filtering.
[0055] In some embodiments, as Figure 4 As shown, the filtering circuit also includes:
[0056] The impedance adjustment module 401 has a first end electrically connected to the second end of the first filter module 201 , and a second end electrically connected to the display device.
[0057] Here, as Figure 4 As shown, the impedance adjustment module may include a resistor R2. Here, in some examples, R2 may be an adjustable resistor. By adjusting the resistance value of R2, the impedance input to the above-mentioned filter circuit can be matched with the impedance of the output circuit for outputting the output signal in the detection device and the impedance of the transmission circuit in the display device. This can suppress the reflection of the signal in the above-mentioned output circuit, filter circuit and transmission circuit, improve the signal transmission efficiency, and setting R2 to be adjustable can enable the above-mentioned filter circuit to receive output signals output by different detection devices, so that the filter circuit can filter the output signals of different detection devices.
[0058] In some embodiments, as Figure 4 As shown, the filtering circuit may further include:
[0059] The third filtering module 402 has a first end electrically connected to the first end of the second filtering module 202 , and a second end electrically connected to the display device.
[0060] like Figure 4The third filter module can include a third capacitor C3, and the third filter module can further realize filtering and improve filtering effect by being arranged.
[0061] Those skilled in the art should understand that the above discussion of any embodiment is only exemplary and is not intended to limit the scope of the present application (including claims) to these examples; the above embodiments or technical features in different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes of different aspects of the embodiments of the present application as described above, which are not provided in details for the sake of brevity.
[0062] The functional blocks shown in the structure block diagram described above can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, a plug-in, a functional card, etc. When implemented in software, the elements of the present application are program or code segments used to perform the required tasks. The program or code segments can be stored in a machine-readable medium or transmitted through a data signal carried in a carrier wave over a transmission medium or communication link. The "machine-readable medium" can include any medium capable of storing or transmitting information. Examples of the machine-readable medium include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segments can be downloaded via a computer network such as the Internet, an intranet, etc.
[0063] It should also be noted that the exemplary embodiments mentioned in the present application describe some methods or devices based on a series of steps or devices. However, the present application is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiments, or different from the order in the embodiments, or several steps are performed simultaneously.
[0064] The computer program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other processing device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other processing device to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.
[0065] The above description is only specific implementation of the present application. For the convenience and brevity of description, the specific working process of the above-described device, module and unit can refer to the corresponding process in the foregoing method embodiments, which will not be described herein. It should be understood that the protection scope of the present application is not limited in this way. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical range disclosed in the present application, and these modifications or replacements should be covered within the protection scope of the present application.
Claims
1. A filter circuit, characterized by, The detection device applied to wafer manufacturing, the circuit comprises: A first filter module, a first end of the first filter module is electrically connected with an output signal end of the detection device, and a second end of the first filter module is electrically connected with a display device, so as to filter out signals lower than or equal to a first frequency; A second filter module, the second filter module is connected in parallel with the first filter module between the output signal end and the display device, so as to filter out signals higher than or equal to a second frequency, the second frequency is greater than the first frequency.
2. The filter circuit of claim 1, wherein, The first filter module comprises at least one first filter submodule, and the at least one first filter submodule is connected in series between the output signal end and the display device.
3. The filter circuit of claim 2, wherein, The first filter submodule comprises: A first filter unit, a first end of the first filter unit is electrically connected with the output signal end; A second filter unit, a first end of the second filter unit is electrically connected with a second end of the first filter unit and a reference voltage end.
4. The filter circuit of claim 3, wherein, The first filter unit comprises a resistor, and the second filter unit comprises a first capacitor.
5. The filter circuit of claim 1, wherein, The second filter module comprises at least one second filter submodule, and the at least one second filter submodule is connected in series between the output signal end and the display device.
6. The filter circuit of claim 5, wherein, The second filter submodule comprises: A third filter unit, a first end of the third filter unit is electrically connected with the output signal end; A fourth filter unit, a first end of the fourth filter unit is electrically connected with a second end of the third filter unit and a reference voltage end.
7. The filter circuit of claim 6, wherein, The third filter unit comprises an inductor, and the fourth filter unit comprises a second capacitor.
8. The filter circuit of claim 1, wherein, The filter circuit further comprises: An impedance adjusting module, a first end of the impedance adjusting module is electrically connected with the second end of the first filter module, and a second end of the impedance adjusting module is electrically connected with the display device.
9. The filter circuit according to any one of claims 1 to 8, characterized in that The filter circuit further comprises: A third filter module, a first end of the third filter module is electrically connected with a first end of the second filter module, and a second end of the third filter module is electrically connected with the display device.
10. A wafer inspection system, characterized by, Comprise: A detection device, a display device and the filter circuit according to any one of claims 1 to 9.