Temperature control device for controlling temperature of measuring objective lens and measuring equipment

Abstract

The application provides a temperature control device for controlling the temperature of a measuring objective lens and a measuring device. The temperature control device comprises a temperature sensor arranged at the measuring objective lens and configured to detect the temperature of the measuring objective lens; and a semiconductor refrigerator which is annularly arranged outside the side wall of the measuring objective lens and comprises a first end close to the measuring objective lens and a second end away from the measuring objective lens. The semiconductor refrigerator is configured to heat or cool the measuring objective lens based on the temperature of the measuring objective lens detected by the temperature sensor, so that the difference between the temperature of the measuring objective lens and a preset temperature is within a preset range. The application can improve the accuracy of the measuring result.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and more specifically to a temperature control device and measuring equipment for controlling the temperature of a measuring objective lens. Background Technology

[0002] Overlay accuracy (OVL) is a core parameter in semiconductor manufacturing that measures the alignment accuracy of patterns in different process layers, directly affecting chip performance and yield.

[0003] Image-based overlay (IBO) measurement equipment directly photographs alignment marks (such as frames within frames, lines within lines) using a high-resolution optical microscope, analyzes the symmetry to calculate the offset, and obtains the overlay accuracy.

[0004] However, IBO measurement equipment in related technologies is prone to drift in the measured overlay accuracy data during measurement, such as an upward trend in the overlay accuracy data, leading to inaccurate measurement results.

[0005] Therefore, improvements are needed to at least partially address the aforementioned problems. Utility Model Content

[0006] The utility model description section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This utility model description section is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0007] To address the existing problems, this application provides a temperature control device for controlling the temperature of a measuring objective lens, comprising:

[0008] A temperature sensor is disposed at the measuring objective lens to detect the temperature of the measuring objective lens;

[0009] A semiconductor cooler is sleeved around the sidewall of the measuring objective lens, including a first end close to the measuring objective lens and a second end away from the measuring objective lens. The semiconductor cooler is used to heat or cool the measuring objective lens based on the temperature of the measuring objective lens detected by the temperature sensor, so that the difference between the temperature of the measuring objective lens and the preset temperature is within a preset range.

[0010] For example, there is a gap between the semiconductor cooler and the sidewall of the measuring objective.

[0011] For example, the width of the gap ranges from 0.5mm to 1cm.

[0012] For example, the measuring objective lens is provided with a first lens and a second lens at both ends along its length. The measuring objective lens passes through the lens fixing member from the end where the second lens is located and is connected to the lens fixing member. The temperature sensor is located at the first lens. The semiconductor cooler is sleeved on the side wall of the measuring objective lens from the end where the first lens is located.

[0013] For example, it also includes a housing fastener, which is sleeved on the side wall of the measuring objective and connected to the lens fastener, and the semiconductor cooler is connected to the housing fastener at one end along the length of the measuring objective near the housing fastener.

[0014] For example, the length of the semiconductor cooler along the longitudinal direction of the measuring objective lens is equal to the length of the sidewall of the measuring objective lens exposed from the housing fixture; and / or

[0015] The ratio of the length of the semiconductor cooler along the length of the measuring objective to the length of the sidewall of the measuring objective is greater than or equal to 2 / 3.

[0016] Exemplarily, the housing fastener is connected to the lens fastener by screws; and / or

[0017] The semiconductor cooler is connected to the housing fastener by screws and / or adhesive.

[0018] For example, the semiconductor cooler includes:

[0019] An annular first thermally conductive substrate is sleeved on the outside of the sidewall of the measuring objective lens;

[0020] A ring-shaped second thermally conductive substrate is sleeved on the first thermally conductive substrate;

[0021] Multiple P-type semiconductors and multiple N-type semiconductors are disposed between the first thermally conductive substrate and the second thermally conductive substrate, and are staggered along the circumferential direction;

[0022] Multiple first conductive layers and multiple second conductive layers are staggered along the circumferential direction and electrically connected to adjacent P-type semiconductors and N-type semiconductors, wherein the first conductive layer is disposed between the P-type semiconductor and the first thermally conductive substrate and between the N-type semiconductor and the first thermally conductive substrate, and the second conductive layer is disposed between the P-type semiconductor and the second thermally conductive substrate and between the N-type semiconductor and the second thermally conductive substrate.

[0023] For example, the preset range is -0.01℃ to 0.01℃.

[0024] Another aspect of this application provides a measuring device, comprising:

[0025] Measurement objective lens;

[0026] The aforementioned temperature control device for controlling the temperature of the measuring objective lens.

[0027] The temperature control device and measuring equipment for controlling the temperature of the measuring objective lens in this application embodiment detect the temperature of the measuring objective lens by means of a temperature sensor. Based on the temperature of the measuring objective lens detected by the temperature sensor, the measuring objective lens is heated or cooled by a semiconductor cooler so that the difference between the temperature of the measuring objective lens and the preset temperature is within a preset range. This can avoid changes in the internal optical path structure of the measuring objective lens due to temperature changes, prevent the measurement results from drifting, and thus improve the accuracy of the measurement results. Attached Figure Description

[0028] The following drawings, which are incorporated herein by reference and are used to understand this application, illustrate embodiments of the invention and their descriptions, thereby explaining the apparatus and principles of the invention.

[0029] In the attached image:

[0030] Figure 1 A bottom view of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application is shown;

[0031] Figure 2 A perspective view of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application is shown;

[0032] Figure 3 A schematic diagram of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application is shown.

[0033] Figure 4 A cross-sectional view of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application is shown.

[0034] Figure 5 A front view of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application is shown;

[0035] Figure 6 A side view of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application is shown;

[0036] Figure 7 A partial structural schematic diagram of a semiconductor cooler according to a specific embodiment of this application is shown.

[0037] Explanation of reference numerals in the attached figures:

[0038] 110-Semiconductor cooler, 111-First thermally conductive substrate, 112-Second thermally conductive substrate, 113-P-type semiconductor, 114-N-type semiconductor, 115-First conductive layer, 116-Second conductive layer, 120-Gap, 130-Housing fixture, 140-Screw, 150-Measuring objective lens, 151-First lens, 152-Second lens, 160-Lens fixture. Detailed Implementation

[0039] In the following description, numerous specific details are set forth to provide a more thorough understanding of this application. However, it will be apparent to those skilled in the art that this application can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with this application. It should be understood that this application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this application to those skilled in the art. In the accompanying drawings, for clarity, the dimensions and relative dimensions of layers and regions may be exaggerated. The same reference numerals denote the same elements throughout.

[0040] It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or parts, these elements, components, areas, layers, and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or part from another element, component, area, layer, or part. Therefore, without departing from the teachings of this application, the first element, component, area, layer, or part discussed below may be referred to as the second element, component, area, layer, or part.

[0041] Spatial relation terms such as "below," "under," "below," "under," "above," and "above" are used here for convenience to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of devices in use and operation.

[0042] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0043] Embodiments of the utility model are described herein with reference to cross-sectional views that serve as schematic diagrams of preferred embodiments (and intermediate structures) of this application. Thus, variations in the shown shape can be anticipated due to, for example, manufacturing techniques and / or tolerances. Therefore, embodiments of this application should not be limited to the specific shapes shown herein, but include shape deviations due to, for example, manufacturing processes. Consequently, the figures are substantially schematic, and their shapes are not intended to show the actual shape of the device and are not intended to limit the scope of this application.

[0044] The related IBO measurement equipment includes a measurement objective lens positioned above the wafer under test. Light is incident on the surface of the wafer under test through the measurement objective lens, and then reflected by the wafer under test and collected after passing through the measurement objective lens.

[0045] However, the inventors of this application discovered that the temperature of the measuring objective lens differs between its idle state and its measurement state. The temperature of the measuring objective lens is lower when idle than during measurement; that is, the temperature of the measuring objective lens rises after measurement begins. The end of the measuring objective lens closest to the wafer being measured experiences the greatest temperature increase.

[0046] The temperature rise of the measurement objective during measurement can cause changes in the internal optical path structure of the measurement objective, such as the relative position shift of the optical elements inside the measurement objective. This can affect the overall optical path of the IBO measurement equipment, leading to drift in the measurement results and inaccurate results.

[0047] Therefore, in view of the aforementioned technical problems, this application proposes a temperature control device for controlling the temperature of a measuring objective lens, comprising:

[0048] A temperature sensor is located at the measuring objective lens to detect the temperature of the measuring objective lens;

[0049] A semiconductor cooler, surrounding and sleeved around the sidewall of the measuring objective lens, includes a first end close to the measuring objective lens and a second end away from the measuring objective lens. The semiconductor cooler is used to heat or cool the measuring objective lens based on the temperature of the measuring objective lens detected by the temperature sensor, so that the difference between the temperature of the measuring objective lens and the preset temperature is within a preset range.

[0050] The temperature control device for controlling the temperature of the measurement objective lens in this application embodiment detects the temperature of the measurement objective lens through a temperature sensor. Based on the temperature of the measurement objective lens detected by the temperature sensor, the measurement objective lens is heated or cooled by a semiconductor cooler so that the difference between the temperature of the measurement objective lens and the preset temperature is within a preset range. This achieves precise temperature control of the measurement objective lens, avoids changes in the internal optical path structure of the measurement objective lens due to temperature changes, prevents drift in the measurement results, and thus improves the accuracy of the measurement results.

[0051] Below, for reference Figures 1 to 6 This application provides a detailed description of the temperature control device for controlling the temperature of a measuring objective lens, wherein... Figure 1 This illustration shows a bottom view of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application. Figure 2 This paper shows a perspective view of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application. Figure 3 This invention illustrates a schematic diagram of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application. Figure 4 A cross-sectional view of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application is shown. Figure 5 This paper shows a front view of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application. Figure 6 A side view of a temperature control device for controlling the temperature of a measuring objective lens according to a specific embodiment of this application is shown. Figure 7 A partial structural schematic diagram of a semiconductor cooler according to a specific embodiment of this application is shown.

[0052] In one example, such as Figures 1 to 6As shown, the temperature control device for controlling the temperature of a measurement objective lens according to this application includes a temperature sensor (not shown) and a thermoelectric cooler (TEC) 110. The temperature sensor is disposed at the measurement objective lens 150 and is used to detect the temperature of the measurement objective lens 150. The thermoelectric cooler 110 is sleeved around the sidewall of the measurement objective lens 150, including a first end near the measurement objective lens 150 and a second end away from the measurement objective lens 150. The thermoelectric cooler 110 is used to heat or cool the measurement objective lens 150 based on the temperature detected by the temperature sensor, so that the difference between the temperature of the measurement objective lens 150 and a preset temperature is within a preset range. More specifically, the thermoelectric cooler 110 is controlled to heat or cool the measurement objective lens 150 based on the difference between the temperature detected by the temperature sensor and the preset temperature. Exemplarily, along the length direction of the measurement objective lens 150, the thermoelectric cooler 110 surrounds a portion of the length of the sidewall of the measurement objective lens 150.

[0053] In one example, the temperature sensor may be located at any suitable position inside or outside the measuring objective 150, for example, inside or outside one end of the measuring objective 150 along its length, or inside or outside the sidewall of the measuring objective 150.

[0054] In one example, the preset temperature and preset range can be reasonably set according to actual needs, and this application does not limit them; preferably, the preset temperature can be set to the temperature of the measuring objective lens 150 when it is idle, and the preset range is -0.01℃ to 0.01℃.

[0055] In one example, the measuring objective 150 is cylindrical and includes a cavity enclosed by lenses at both ends along its length and sidewalls, as well as a plurality of lenses disposed within the cavity.

[0056] In one example, the measurement objective mentioned in this application can be used in a measurement device, such as the IBO measurement device described below, to measure the overlay accuracy of the wafer under test. Specifically, the measurement objective of this application is positioned above the wafer under test during measurement.

[0057] In one example, a thermoelectric cooler is a semiconductor device based on the Peltier effect. It can switch between cooling and heating functions by changing the direction of the current inside it. The Peltier effect refers to the phenomenon that when a direct current passes through a thermocouple composed of two semiconductor materials (P-type semiconductor and N-type semiconductor), one end of the thermocouple absorbs heat and the other end releases heat (the end that absorbs heat is the cold end and the end that releases heat is the hot end). Therefore, a thermoelectric cooler is also called a thermoelectric cooler.

[0058] The temperature control device for controlling the temperature of the measurement objective lens in this application may further include a power source for supplying current to the semiconductor cooler 110. The direction of the current supplied to the semiconductor cooler 110 is either a first direction or a second direction. When the direction of the current is the first direction, the first end is the cold end and the second end is the hot end, and the semiconductor cooler is used to cool the measurement objective lens. When the direction of the current is the second direction, the first end is the hot end and the second end is the cold end, and the semiconductor cooler is used to heat the measurement objective lens. Specifically, by controlling the direction of the current supplied to the semiconductor cooler 110 to be the first direction, making the first end the cold end and the second end the hot end, heat is absorbed through the first end and released through the second end, with the heat flow direction from the first end to the second end, enabling the semiconductor cooler to cool the measurement objective lens. By controlling the direction of the current supplied to the semiconductor cooler 110 to be the first direction, making the first end the hot end and the second end the cold end, heat is absorbed through the second end and released through the first end, with the heat flow direction from the second end to the first end, enabling the semiconductor cooler to heat the measurement objective lens. For example, a power supply is electrically connected to the thermoelectric cooler 110 to supply direct current to the thermoelectric cooler 110.

[0059] In one example, taking a preset range of -0.01℃ to 0.01℃ as an example, the temperature of the measurement objective is detected by a temperature sensor. When the difference between the detected temperature and the preset temperature is less than -0.01℃, the direction of the current flowing into the thermoelectric cooler is controlled to a second direction, so that the thermoelectric cooler heats the measurement objective until the difference between the temperature detected by the temperature sensor and the preset temperature returns to the preset range. When the difference between the detected temperature and the preset temperature is greater than 0.01℃, the direction of the current flowing into the thermoelectric cooler is controlled to a first direction, so that the thermoelectric cooler cools the measurement objective until the difference between the temperature detected by the temperature sensor and the preset temperature returns to the preset range. In this way, through the cooperation of the temperature sensor and the thermoelectric cooler, precise temperature control of the measurement objective can be achieved, avoiding changes in the internal optical path structure of the measurement objective due to temperature changes, preventing drift in the measurement results, and thus improving the accuracy of the measurement results.

[0060] In one example, the temperature control device for controlling the temperature of the measurement objective lens according to this application may further include a processor connected to the signal output terminal of a temperature sensor. The processor receives the temperature of the measurement objective lens 150 collected by the temperature sensor, compares it with a preset temperature, and controls the direction of the current flowing into and thus controlling the thermoelectric cooler based on the comparison result, thereby causing the thermoelectric cooler 110 to heat or cool the measurement objective lens 150. Exemplarily, the processor can be implemented as software, hardware, firmware, or any combination thereof, and may use one or more application-specific integrated circuits (ASICs), one or more general-purpose integrated circuits, one or more microprocessors, one or more programmable logic devices, or any combination of the aforementioned circuits and / or devices, or other suitable circuits or devices.

[0061] In one example, such as Figure 1 , Figure 3 and Figure 4 As shown, a gap 120 exists between the thermoelectric cooler 110 and the sidewall of the measuring objective lens 150, preventing direct contact between them. This avoids the thermoelectric cooler 110 applying external force to the measuring objective lens 150, which could cause deformation and consequently alter the internal optical path structure. Furthermore, the gap 120 between the thermoelectric cooler 110 and the sidewall of the measuring objective lens 150 also prevents the thermoelectric cooler 110 from applying external force to the measuring objective lens 150 due to the difference in their coefficients of thermal expansion during temperature changes.

[0062] In one example, the width of the gap 120 (width in the radial direction) ranges from 0.5 mm to 1 cm. For example, the width of the gap 120 can be 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 1 cm. The smaller the width of the gap 120, the better the temperature control effect (heating and cooling effect) of the thermoelectric cooler 110 on the measuring objective lens 150. The larger the width of the gap 120, the easier it is to mount the thermoelectric cooler 110 on the sidewall of the measuring objective lens 150. Preferably, the width of the gap 120 is in the range of 0.5 mm to 1 mm. In other embodiments, the width of the gap 120 can be any other suitable range, and this application does not limit this.

[0063] In one example, such as Figure 1 , Figure 2 and Figure 3As shown, the measuring objective lens 150 has a first lens 151 and a second lens 152 at its two ends along its length. The measuring objective lens 150 passes through and is connected to the lens fixing member 160 from the end where the second lens 152 is located. A temperature sensor is located at the first lens 151, and a semiconductor cooler 110 is sleeved on the side wall of the measuring objective lens 150 from the end where the first lens 151 is located. The fact that the measuring objective lens 150 passes through and is connected to the lens fixing member 160 from the end where the second lens 152 is located, to fix the measuring objective lens 150, is a conventional arrangement in the art and will not be described in detail here. It is worth noting that along the length of the measuring objective lens 150, the lens fixing member 160 surrounds a portion of the side wall of the measuring objective lens 150 from the end where the second lens 152 is located. For example, along the length of the measuring objective lens 150, the semiconductor cooler 110 extends from the end where the first lens 151 is located to surround a portion of the sidewall of the measuring objective lens 150.

[0064] In one example, during measurement, the first lens 151 is close to the wafer under test while the second lens 152 is far away. The temperature change at the first lens 151 is the largest. By placing a temperature sensor at the first lens 151, the temperature at the first lens 151 can be detected in real time. Simultaneously, a semiconductor cooler 110 is fitted onto the side wall of the measurement objective lens 150 from the end where the first lens 151 is located, enabling better temperature control at the first lens 151, thereby improving the temperature control effect of the measurement objective lens 150. For example, ensuring that the temperature difference between the measurement objective lens and the preset temperature is within a preset range means that the temperature difference between the first lens and the preset temperature is within the preset range.

[0065] In one example, such as Figures 1 to 5 As shown, the temperature control device for controlling the temperature of the measuring objective lens of this application further includes a housing fixing member 130. The housing fixing member 130 is sleeved on the side wall of the measuring objective lens 150 and connected to the lens fixing member 160. The end of the semiconductor cooler 110 along the length direction of the measuring objective lens 150 near the housing fixing member 130 is connected to the housing fixing member 130. Exemplarily, the housing fixing member 130 is used to fix the semiconductor cooler 110; the housing fixing member 130 can be made of any suitable material, such as an alloy, etc., and this application does not limit it in this regard.

[0066] In one example, such as Figure 1 and Figure 2As shown, the housing fastener 130 is connected to the lens fastener 160 by screws 140. Specifically, the housing fastener 130 is connected to the two side walls of the lens fastener 160 by four screws 140. In other embodiments, the housing fastener 130 can also be connected to the lens fastener 160 by other means, such as bonding, etc. This application does not limit this.

[0067] In one example, the thermoelectric cooler 110 is connected to the housing fastener 130 by screws and / or adhesive. Specifically, the thermoelectric cooler 110 is connected to the housing fastener 130 at one end along the length of the measuring objective lens 150 near the housing fastener 130 by screws and / or adhesive. In other embodiments, the thermoelectric cooler 110 may also be connected to the housing fastener 130 in other ways, which are not limited in this application.

[0068] In one example, such as Figures 2 to 6 As shown, the length of the semiconductor cooler 110 along the length direction of the measuring objective lens 150 is equal to the length of the side wall of the measuring objective lens 150 exposed from the housing fixture 130. That is, along the length direction of the measuring objective lens 150, the length of the side wall of the measuring objective lens 150 surrounded by the semiconductor cooler 110 is equal to the length of the side wall of the measuring objective lens 150 from the housing fixture 130 to the first lens 151, so as to improve the temperature control effect of the measuring objective lens 150.

[0069] In one example, the ratio of the length of the thermoelectric cooler 110 along the length direction of the measuring objective lens 150 to the length of the sidewall of the measuring objective lens 150 is greater than or equal to 2 / 3. That is, along the length direction of the measuring objective lens 150, the ratio of the length of the sidewall of the measuring objective lens 150 surrounded by the thermoelectric cooler 110 to the length of the sidewall of the measuring objective lens 150 is greater than or equal to 2 / 3, thus improving the temperature control effect on the measuring objective lens 150. Exemplarily, the ratio of the length of the thermoelectric cooler 110 along the length direction of the measuring objective lens 150 to the length of the sidewall of the measuring objective lens 150 is also less than 1.

[0070] In one example, such as Figure 7As shown, the semiconductor cooler 110 includes an annular first thermally conductive substrate 111, an annular second thermally conductive substrate 112, a plurality of P-type semiconductors 113, a plurality of N-type semiconductors 114, a plurality of first conductive layers 115, and a plurality of second conductive layers 116, wherein: the first thermally conductive substrate 111 is sleeved on the sidewall of the measuring objective lens 150; the second thermally conductive substrate 112 is sleeved on the first thermally conductive substrate 111; and the plurality of P-type semiconductors 113 and the plurality of N-type semiconductors 114 are disposed between the first thermally conductive substrate 111 and the second thermally conductive substrate 112. The first conductive layer 115 and the second conductive layer 116 are staggered along the circumferential direction and electrically connected to adjacent P-type semiconductors 113 and N-type semiconductors 114. The first conductive layer 115 is disposed between the P-type semiconductor 113 and the first thermally conductive substrate 111, and between the N-type semiconductor 114 and the first thermally conductive substrate 111. The second conductive layer 116 is disposed between the P-type semiconductor 113 and the second thermally conductive substrate 112, and between the N-type semiconductor 114 and the second thermally conductive substrate 112. Exemplarily, the first thermally conductive substrate 111 constitutes the first end of the semiconductor cooler, and the second thermally conductive substrate 112 constitutes the second end of the semiconductor cooler.

[0071] In one example, the side of the first conductive layer 115 closest to the measuring objective lens 150 is connected to the first thermally conductive substrate 111, and the side of the second conductive layer 116 furthest from the measuring objective lens 150 is connected to the second thermally conductive substrate 112. The first conductive layer 115, the second conductive layer 116, the P-type semiconductor 113, and the N-type semiconductor 114 together form a conductive path. The first thermally conductive substrate 111 and the second thermally conductive substrate 112 then conduct heat to achieve heat exchange with the outside environment. Here, the P-type semiconductor and the N-type semiconductor refer to semiconductors with P-type conductivity (majority carriers are holes) and semiconductors with N-type conductivity (majority carriers are electrons), respectively. Exemplarily, the first thermally conductive substrate 111 and the second thermally conductive substrate 112 have the same length along the length direction of the measuring objective lens 150, and the length of the semiconductor cooler mentioned above refers to the length of the first thermally conductive substrate 111 and the second thermally conductive substrate 112.

[0072] Exemplary, the materials of the first thermally conductive substrate 111 and the second thermally conductive substrate 112 can be any suitable material, such as ceramic, and this application does not impose any limitations on this. Exemplary, the first thermally conductive substrate 111 and the second thermally conductive substrate 112 also have an insulating function. Exemplary, the materials of the first conductive layer 115 and the second conductive layer 116 can be any suitable conductive material, such as copper, nickel, etc., and this application does not impose any limitations on this.

[0073] This concludes the description of the structure of the temperature control device for controlling the temperature of the measuring objective lens according to this application. A complete temperature control device for controlling the temperature of the measuring objective lens may also include other components, which will not be described in detail here.

[0074] In summary, the temperature control device for controlling the temperature of the measurement objective lens in this application embodiment detects the temperature of the measurement objective lens through a temperature sensor. Based on the temperature of the measurement objective lens detected by the temperature sensor, the measurement objective lens is heated or cooled by a semiconductor cooler to ensure that the temperature difference between the measurement objective lens and the preset temperature is within a preset range. This can avoid changes in the internal optical path structure of the measurement objective lens due to temperature changes, prevent the measurement results from drifting, and thus improve the accuracy of the measurement results.

[0075] This application also provides a measurement device, which includes a measurement objective lens and the temperature control device described above for controlling the temperature of the measurement objective lens. Exemplarily, the complete measurement device may also include other components, such as a support stage for supporting the wafer to be measured, which will not be elaborated upon here.

[0076] The measurement equipment in this application can be any suitable measurement equipment known to those skilled in the art. For example, the measurement equipment in this application can be a measurement equipment used to measure the overlay accuracy of the wafer under test (e.g., an IBO measurement equipment).

[0077] In one example, taking an IBO measurement device as an example, the measurement device of this application may further include a beam splitter (e.g., a dichroic mirror), a reference objective, and a reference mirror. The beam splitter can transmit and reflect part of the light. When measuring the overlay accuracy of the wafer under test, the measurement optical path is as follows: the light emitted from the light source is incident on the beam splitter, and part of the light is reflected by the beam splitter, focused by the measurement objective, and then incident on the surface of the wafer under test. After being reflected by the wafer under test and collimated by the measurement objective, the light is incident on the beam splitter, and part of the light is transmitted by the beam splitter and collected. The reference objective and the reference mirror constitute the reference optical path, which is used to achieve white light interference with the measurement optical path and to assist in the rapid adjustment of the measurement optical path. The reference optical path is as follows: the light emitted from the light source is incident on the beam splitter. Part of the light is transmitted by the beam splitter, collimated by the reference objective, and then incident on the reference mirror. After being reflected by the reference mirror, it is collimated again by the reference mirror and then incident on the beam splitter.

[0078] The measurement device of this application embodiment includes a measurement objective lens and the temperature control device for controlling the temperature of the measurement objective lens as described above. The temperature of the measurement objective lens is detected by a temperature sensor. Based on the temperature of the measurement objective lens detected by the temperature sensor, the measurement objective lens is heated or cooled by a semiconductor cooler so that the difference between the temperature of the measurement objective lens and the preset temperature is within a preset range. This achieves precise temperature control of the measurement objective lens, avoids changes in the internal optical path structure of the measurement objective lens due to temperature changes, prevents drift in the measurement results, and thus improves the accuracy of the measurement results.

[0079] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of this application. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of this application. All such changes and modifications are intended to be included within the scope of this application as claimed in the appended claims.

[0080] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0081] Similarly, it should be understood that, in order to streamline this application and aid in understanding one or more of the various aspects of the invention, features of this application may sometimes be grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of this application. However, this approach should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, the inventive point lies in solving the corresponding technical problem with fewer features than all of those in a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0082] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or elements of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature serving the same, equivalent, or similar purpose.

[0083] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0084] It should be noted that the above embodiments are illustrative of this application and not restrictive of this application, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims.

Claims

1. A temperature control device for controlling the temperature of a measuring objective lens, characterized in that, include: A temperature sensor is disposed at the measuring objective lens to detect the temperature of the measuring objective lens; A semiconductor cooler is sleeved around the sidewall of the measuring objective lens, including a first end close to the measuring objective lens and a second end away from the measuring objective lens. The semiconductor cooler is used to heat or cool the measuring objective lens based on the temperature of the measuring objective lens detected by the temperature sensor, so that the difference between the temperature of the measuring objective lens and the preset temperature is within a preset range.

2. The temperature control device according to claim 1, characterized in that, There is a gap between the semiconductor cooler and the sidewall of the measuring objective lens.

3. The temperature control device according to claim 2, characterized in that, The width of the gap ranges from 0.5mm to 1cm.

4. The temperature control device according to any one of claims 1-3, characterized in that, The measuring objective lens is provided with a first lens and a second lens at both ends along its length. The measuring objective lens passes through the lens fixing member from the end where the second lens is located and is connected to the lens fixing member. The temperature sensor is located at the first lens. The semiconductor cooler is sleeved on the side wall of the measuring objective lens from the end where the first lens is located.

5. The temperature control device according to claim 4, characterized in that, It also includes a housing fixing component, which is sleeved on the side wall of the measuring objective lens and connected to the lens fixing component. The semiconductor cooler is connected to the housing fixing component at one end along the length direction of the measuring objective lens near the housing fixing component.

6. The temperature control device according to claim 5, characterized in that, The length of the semiconductor cooler along the length of the measuring objective lens is equal to the length of the sidewall of the measuring objective lens exposed from the housing fixture. and / or The ratio of the length of the semiconductor cooler along the length direction of the measuring objective to the length of the sidewall of the measuring objective is greater than or equal to 2 / 3.

7. The temperature control device according to claim 5, characterized in that, The housing fastener is connected to the lens fastener by screws; and / or The semiconductor cooler is connected to the housing fastener by screws and / or adhesive.

8. The temperature control device according to any one of claims 1-3, characterized in that, The semiconductor cooler includes: An annular first thermally conductive substrate is sleeved on the outside of the sidewall of the measuring objective lens; A ring-shaped second thermally conductive substrate is sleeved on the first thermally conductive substrate; Multiple P-type semiconductors and multiple N-type semiconductors are disposed between the first thermally conductive substrate and the second thermally conductive substrate, and are staggered along the circumferential direction; Multiple first conductive layers and multiple second conductive layers are staggered along the circumferential direction and electrically connected to adjacent P-type semiconductors and N-type semiconductors, wherein the first conductive layer is disposed between the P-type semiconductor and the first thermally conductive substrate and between the N-type semiconductor and the first thermally conductive substrate, and the second conductive layer is disposed between the P-type semiconductor and the second thermally conductive substrate and between the N-type semiconductor and the second thermally conductive substrate.

9. The temperature control device according to any one of claims 1-3, characterized in that, The preset range is -0.01℃ to 0.01℃.

10. A measuring device, comprising: Measurement objective lens; A temperature control device for controlling the temperature of a measuring objective lens according to any one of claims 1-9.

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