PID (Proportion Integration Differentiation)-controlled sample temperature adjusting table

Abstract

The utility model discloses a PID-controlled sample temperature adjusting table, and relates to the technical field of ellipsometry, the sample temperature adjusting table comprises a sample table, a first driving part and a second driving part, the sample table is provided with a PID temperature controller, and the PID temperature controller is used for adjusting the temperature of the sample table; the sample table is arranged at the output end of the second driving part, the output end of the second driving part can move in the horizontal direction, the second driving part is arranged at the output end of the first driving part, the output end of the first driving part moves in the horizontal direction, and the moving direction of the output end of the second driving part is perpendicular to the moving direction of the output end of the second driving part. The method and the device have the effect of improving the measurement efficiency of ellipsometry when different samples are continuously measured.

Description

Technical Field

[0001] The present application relates to the technical field of ellipsometry measurement, and in particular to a PID-controlled sample temperature regulating stage. Background Art

[0002] Ellipsometry is a method of measuring film thickness, refractive index, surface roughness, lattice structure and anisotropy using an ellipsometer. The data obtained by ellipsometric measurement can be used to analyze parameters such as optical constants and film thickness. The advantage of the relative interferometry method of ellipsometric measurement is that it does not require contact with the sample, does not damage the sample, and does not require a vacuum environment. Therefore, ellipsometric measurement is widely used in laboratory research, the semiconductor industry, and the optical coating industry.

[0003] The ellipsometer includes a sample stage and a measuring component. A temperature control component is provided in the sample stage. The temperature control component includes a control module, a heating wire, a cooling component and a temperature sensor which are electrically connected to each other. When measuring ellipsometric, the initial incident angle of the measuring component is first corrected, and then the sample is placed on the sample stage. The temperature sensor collects the temperature information of the sample stage, and controls the heating wire to heat the sample stage through the control module, so that the temperature of the sample stage is maintained at the temperature required for the measurement. Then the measuring component measures the sample. After the measurement is completed, the heating wire stops heating, and the cooling component cools the sample stage, so that the temperature of the sample stage drops to room temperature.

[0004] However, when measuring different samples, after each sample is measured, the sample stage needs to be cooled to room temperature before placing another sample on it to avoid the experimenter being burned by the high-temperature sample stage when placing the sample. The cooling time is long, so when the ellipsometer measures different samples, the total measurement time is longer and the measurement efficiency is slower. Utility Model Content

[0005] In order to improve the measurement efficiency of ellipsometry when continuously measuring different samples, the present application provides a PID-controlled sample temperature adjustment stage.

[0006] The present application provides a PID-controlled sample temperature adjustment table, which adopts the following technical solution:

[0007] A PID-controlled sample temperature regulating platform, comprising:

[0008] A sample stage, wherein the sample stage is provided with a PID temperature controller, and the PID temperature controller is used to adjust the temperature of the sample stage;

[0009] A first driving member and a second driving member, wherein the sample stage is arranged at an output end of the second driving member, and the output end of the second driving member can move in a horizontal direction; the second driving member is arranged at an output end of the first driving member, and the output end of the first driving member moves in a horizontal direction, and the moving direction is perpendicular to the moving direction of the output end of the second driving member.

[0010] By adopting the above technical solution, when performing ellipsometric measurement, the operator places multiple samples to be measured on the sample stage, and then performs ellipsometric measurement on the multiple samples to be measured in sequence. When the measurement of one sample to be measured is completed, the first driving member and the second driving member drive the sample stage to move, so that the next sample to be measured moves to the measurement position, and then performs ellipsometric measurement on the sample to be measured at the measurement position, which saves the time required for cooling the sample stage, thereby improving the measurement efficiency.

[0011] Optionally, a third driving member is connected between the output end of the first driving member and the sample stage, and the third driving member is used to drive the sample stage to move in a vertical direction.

[0012] By adopting the above technical solution, when the sample to be tested is a film with a certain thickness, the third driving member can drive the sample stage to move in the vertical direction, thereby facilitating the adjustment of the height of the sample to be tested and facilitating the measurement of the sample to be tested.

[0013] Optionally, a fourth driving member and a fifth driving member are connected between the sample stage and the first driving member, the sample stage is connected to the output end of the fifth driving member, the output end of the fifth driving member is capable of rotating, and the rotation axis is arranged in the horizontal direction, the fifth driving member is connected to the output end of the fourth driving member, the output end of the fourth driving member is capable of rotating, the rotation axis of the output end of the fourth driving member is arranged in the horizontal direction, and is perpendicular to the direction of the rotation axis of the output end of the fifth driving member.

[0014] By adopting the above technical solution, the fourth driver and the fifth driver can adjust the angle of the sample stage, thereby adjusting the initial incident angle of the light, and when the sample stage deviates from the initial position due to human factors or environmental factors, the fourth driver and the fifth driver can fine-tune the sample stage so that the sample to be measured on the sample stage meets the levelness required for measurement, thereby improving the accuracy of ellipsometric measurement.

[0015] Optionally, the sample stage is provided with a plurality of positioning holes, and a positioning assembly is provided corresponding to the positioning holes. The positioning assembly includes a suction head and a sixth driving member. The output end of the suction head is connected to the positioning hole, and the input end of the suction head is connected to the output end of the sixth driving member. The sixth driving member is used to drive the suction head to fix the sample.

[0016] By adopting the above technical solution, when a sample to be measured is measured, the first driving member and the second driving member drive the sample stage to move, and the sample to be measured on the sample stage may be displaced relative to the sample stage due to factors such as small friction or inertia. After installing the positioning component, the tester places the sample to be measured at the positioning hole, and then the suction head generates suction on the sample to be measured through the positioning hole, thereby fixing the sample to be measured and reducing the movement of the sample to be measured relative to the sample stage, thereby improving the measurement accuracy of the ellipsometric measurement and facilitating the adjustment of the position of the sample to be measured. Fixing the sample with the suction head through the positioning hole can reduce the situation where the clamp is higher than the sample when the clamp is used to fix the sample, causing the clamp to block the light path, and can position samples of any shape, which is more flexible.

[0017] Optionally, the sample table includes a base and a storage table, the storage table is installed on the base, the output end of the second driving member is connected to the base, the PID temperature controller includes a heating part, a heat conducting plate is connected between the heating part and the base, and the heat conducting plate is in contact with the storage table.

[0018] By adopting the above technical solution, the heating unit heats the storage table through the heat conducting plate. Since the heat conducting plate has a large area, the storage table is heated evenly, thereby improving the uniformity of heating of the sample to be measured and improving the accuracy of ellipsometric measurement.

[0019] Optionally, a heat insulation component is included, and the heat insulation component includes a first heat insulation part, and the first heat insulation part is respectively connected to the base and the storage table.

[0020] By adopting the above technical solution, the first heat insulation part can reduce the heat transferred from the storage table to the base, reduce the temperature change of the base, thereby reducing the heat transferred from the storage table to the first driving member and the second driving member through the base when the temperature of the storage table is high, reduce the deformation of the first driving member and the second driving member due to high temperature, thereby reducing the impact of heating the storage table on the service life of the first driving member and the service life of the second driving member.

[0021] Optionally, the thermal insulation assembly includes a first positioning portion and a second positioning portion which are parallel to each other, wherein the first positioning portion is arranged inside the first thermal insulation portion, and the second positioning portion is arranged outside the first thermal insulation portion, the storage table is located inside the first thermal insulation portion and abuts against the first positioning portion, and the base is arranged on the outside of the first thermal insulation portion and abuts against the second positioning portion.

[0022] By adopting the above technical solution, the storage table abuts against the first positioning portion, and the base abuts against the second positioning portion, which facilitates the positioning and assembly of the storage table and the base. Since the first positioning portion and the second positioning portion are parallel, the storage table and the base are parallel to each other, thereby reducing the influence of the shape and position errors between the storage table and the base on the accuracy of ellipsometric measurement.

[0023] Optionally, the thermal insulation assembly includes a second thermal insulation portion, which is threadedly connected to the base. When the second thermal insulation portion is connected to the base, the second thermal insulation portion and the first positioning portion jointly press against the storage table.

[0024] By adopting the above technical solution, the connection between the base and the storage table is located in the second insulation part, which can reduce the heat transferred from the storage table to the bolts on the second insulation part when the storage table is heated, thereby reducing the deformation of the bolts on the second insulation part due to temperature changes, and improving the reliability of the connection between the base and the storage table.

[0025] In summary, the present application includes at least one of the following beneficial effects:

[0026] 1. When performing ellipsometric measurement, the operator places multiple samples to be measured on the sample stage, and then performs ellipsometric measurement on the multiple samples to be measured in sequence. When the measurement of one sample to be measured is completed, the first driving member and the second driving member drive the sample stage to move, so that the next sample to be measured moves to the measurement position, and then performs ellipsometric measurement on the sample to be measured at the measurement position, which saves the time required for the sample stage to cool down, thereby improving the measurement efficiency;

[0027] 2. The fourth and fifth driving members can adjust the angle of the sample stage, thereby adjusting the initial incident angle of the light, and when the sample stage deviates from the initial position due to human factors or environmental factors, the fourth and fifth driving members can fine-tune the sample stage so that the sample to be measured on the sample stage meets the levelness required for measurement, thereby improving the accuracy of ellipsometric measurement;

[0028] 3. When the measurement of a sample is completed, the first driving member and the second driving member drive the sample stage to move, and the sample on the sample stage may be displaced relative to the sample stage due to factors such as small friction or inertia. After installing the positioning assembly, the tester places the sample at the positioning hole, and then the suction head generates suction to the sample through the positioning hole, thereby fixing the sample and reducing the movement of the sample relative to the sample stage, thereby improving the measurement accuracy of the ellipsometric measurement and facilitating the adjustment of the position of the sample;

[0029] 4. The first heat insulating portion can reduce the heat transferred from the storage table to the base, reduce the temperature change of the base, thereby reducing the heat transferred from the storage table to the first driving member and the second driving member through the base when the temperature of the storage table is high, reduce the deformation of the first driving member and the second driving member due to high temperature, and thus reduce the impact of heating the storage table on the service life of the first driving member and the service life of the second driving member. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application;

[0031] Figure 2 It is a schematic diagram of the exploded structure of the sample stage used to display the embodiment of the present application.

[0032] Explanation of the accompanying drawings: 1. sample table; 11. storage table; 12. base; 2. first driving member; 3. second driving member; 4. third driving member; 5. fourth driving member; 6. fifth driving member; 7. positioning hole; 8. positioning assembly; 81. suction head; 82. sixth driving member; 9. heating part; 91. heat conduction plate; 10. thermal insulation assembly; 101. first thermal insulation part; 102. first positioning part; 103. second positioning part; 104. second thermal insulation part. DETAILED DESCRIPTION

[0033] Ellipsometry refers to a measurement method that uses an ellipsometer to measure the optical parameters of a sample. The ellipsometer includes a measurement component and a sample stage. The sample stage is located below the measurement component and is used to place the sample and control the temperature of the sample during measurement. The measurement component can emit light to the sample on the sample stage and receive light refracted or reflected by the sample, thereby measuring the various optical parameters of the sample. After the measurement is completed, the sample stage is cooled, and the experimenter replaces the sample on the sample stage and measures the sample on the sample stage.

[0034] The following is combined with Figure 1-2 This application is described in further detail.

[0035] The sample temperature adjustment table of PID control disclosed in the embodiment of the present application is referred to Figure 1 The PID-controlled sample temperature adjustment platform includes a first driving member 2, which is a linear motor. The output end of the first driving member 2 moves in the horizontal direction. The output end of the first driving member 2 is equipped with a second driving member 3, which is a linear motor. The moving direction of the second driving member 3 is horizontal and perpendicular to the moving direction of the output end of the first driving member 2. The output end of the second driving member 3 is equipped with a third driving member 4, which is a linear motor. The moving direction of the output end of the third driving member 4 is vertical. The output end of the third driving member 4 is equipped with a fourth driving member 5. The fourth driving member 5 is a motor. The rotation axis of the output shaft of the fourth driving member 5 is arranged in the horizontal direction. The output end of the fourth driving member 5 is equipped with a fifth driving member 6. The fifth driving member 6 is a motor. The rotation axis of the output end of the fifth driving member 6 is arranged in the horizontal direction and is perpendicular to the rotation axis of the output end of the fourth driving member 5. The output end of the fifth driving member 6 is equipped with a sample stage 1. The sample stage 1 is equipped with a PID temperature controller. The PID temperature controller is used to adjust the temperature of the sample stage 1. The PID temperature controller uses a PID algorithm to control the temperature of the sample stage 1 so that the temperature of the sample stage 1 remains constant.

[0036] Before the ellipsometric measurement, the test personnel place multiple samples on the sample stage 1, and the first driver 2, the second driver 3, and the third driver 4 adjust the position of the sample stage 1 according to the measurement requirements, so that the sample to be measured moves to the position to be measured with the sample stage 1, and then the PID temperature controller maintains the temperature of the sample stage 1 at the temperature required for measurement. When the temperature of the sample on the sample stage 1 is consistent with the temperature of the sample stage 1, the sample is measured for ellipsometric measurement. When the sample measurement is completed, the first driver 2, the second driver 3, and the third driver 4 drive the sample stage 1 to move, so that the next sample to be measured moves to the measurement position, and repeat the above operation to perform ellipsometric measurement on the sample at the measurement position. The first driver 2, the second driver 3, and the third driver 4 drive the sample stage 1 to move, saving part of the cooling time of the sample stage 1 when continuously measuring multiple different samples, thereby improving the measurement efficiency. In addition, the first driver 2, the second driver 3, and the third driver 4 can fine-tune the position of the sample stage 1, thereby correcting the position of the sample stage 1 and improving the measurement accuracy of the ellipsometric measurement.

[0037] The fourth driving member 5 and the fifth driving member 6 can adjust the angle of the sample stage 1, thereby adjusting the initial incident angle according to the measurement requirements, and can adjust the horizontality of the sample stage 1, thereby improving the measurement accuracy of the ellipsometric measurement.

[0038] Reference Figure 2 The sample stage 1 includes a placement table 11 and a base 12. The base 12 is installed at the output end of the fifth driving member 6. A circular groove is formed at one end of the base 12 away from the fifth driving member 6. A heating part 9 is installed in the groove on the base 12. The heating part 9 is an electric heating wire. The placement table 11 is a circular plate. A heat conducting plate 91 is bonded to the bottom wall of the placement table 11. The heat conducting plate 91 is a mica heating plate. The placement table 11 is provided with a plurality of positioning holes 7 around its axis. A positioning assembly 8 is correspondingly provided for each positioning hole 7. The positioning assembly 8 includes a suction head 81 and a sixth driving member 82. The sixth driving member 82 is an air pump. The air pump is installed on the heat conducting plate 91. The suction head 81 is installed at the output end of the sixth driving member 82, and one end of the suction head 81 is located in the positioning hole 7.

[0039] The sample is placed on the stage 11 and covers the positioning hole 7, and then the sixth driving member 82 generates suction through the suction head 81, thereby fixing the sample at the positioning hole 7 of the stage 11, thereby reducing the movement of the sample relative to the stage 11 when the sample stage 1 moves or swings, thereby facilitating the positioning of the sample to the measurement position and improving the measurement accuracy of the ellipsometric measurement.

[0040] When using a clamp to fix the sample, if the clamp is higher than the sample, the clamp may block the light path, causing the tester to need to adjust the position of the sample clamped by the clamp. The suction head 81 fixes the sample through the positioning hole 7 to reduce the situation where the clamp is higher than the sample when using the clamp to fix the sample, causing the clamp to block the light path, and can position samples of any shape, which is more flexible.

[0041] Since the heat conducting plate 91 has a large area, the stage 11 is heated evenly, thereby improving the uniformity of heating of the sample and improving the accuracy of ellipsometric measurement.

[0042] Reference Figure 2 The PID-controlled sample temperature regulating table includes a heat insulation component 10, and the heat insulation component 10 includes a first heat insulation part 101 and a second heat insulation part 104. The first heat insulation part 101 is annular and is located between the base 12 and the storage table 11. The inner wall of the first heat insulation part 101 close to one end of the storage table 11 is fixedly connected with a first positioning part 102, the first positioning part 102 is annular and abuts against the storage table 11, and the outer wall of the first heat insulation part 101 close to one end of the base 12 is fixedly connected with a second positioning part 103, the second positioning part 103 is annular and abuts against the storage table 11, and the first heat insulation part 101, the first positioning part 102 and the second positioning part 103 are all coaxially arranged with the storage table 11. The second heat insulating portion 104 is annular and coaxially arranged with the first heat insulating portion 101. The second heat insulating portion 104 is detachably connected to the base 12 by bolts. When the second heat insulating portion 104 is connected to the base 12, the second heat insulating portion 104 and the first positioning portion 102 are pressed against the storage table 11. The materials of the first heat insulating portion 101, the first positioning portion 102, the second positioning portion 103 and the second heat insulating portion 104 are all heat insulating materials such as asbestos or ceramic wool.

[0043] The thermal insulation assembly 10 can reduce the heat transferred from the storage table 11 to the base 12, reduce the temperature change of the base 12, thereby reducing the heat transferred from the base 12 to the first driving member 2 and the second driving member 3, and reduce the deformation or failure of the first driving member 2 and the second driving member 3 due to high temperature.

[0044] The stage 11 abuts against the first positioning portion 102, and the base 12 abuts against the second positioning portion 103, which facilitates the positioning and assembly of the stage 11 and the base 12. Since the first positioning portion 102 and the second positioning portion 103 are parallel, the stage 11 and the base 12 are parallel to each other, thereby reducing the influence of the shape and position errors between the stage 11 and the base 12 on the accuracy of ellipsometric measurement.

[0045] The second insulation part 104 can reduce the heat transferred from the platform 11 to the bolts on the second insulation part 104 when the platform 11 is heated, thereby reducing the deformation of the bolts on the second insulation part 104 due to temperature changes and improving the reliability of the connection between the base 12 and the platform 11.

[0046] The implementation principle of a PID-controlled sample temperature adjustment stage in an embodiment of the present application is as follows: during ellipsometry measurement, the sample stage 1 needs to be heated so that the temperature of the sample stage 1 is maintained at the temperature required for the measurement. The first driving member 2 and the second driving member 3 can control the movement of the sample stage 1 after the test is completed to move the sample on the sample stage 1 to the measurement position, thereby saving some of the time required for cooling the sample stage 1 when replacing the sample, and improving the measurement efficiency when continuously measuring different samples.

[0047] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A PID-controlled sample temperature adjustment table, characterized in that: include: A sample stage (1), wherein the sample stage (1) is provided with a PID temperature controller, and the PID temperature controller is used to adjust the temperature of the sample stage (1); A first driving member (2) and a second driving member (3), wherein the sample stage (1) is arranged at the output end of the second driving member (3), and the output end of the second driving member (3) can move in a horizontal direction; the second driving member (3) is arranged at the output end of the first driving member (2), and the output end of the first driving member (2) moves in a horizontal direction, and the moving direction is perpendicular to the moving direction of the output end of the second driving member (3).

2. A PID-controlled sample temperature adjustment platform according to claim 1, characterized in that: A third driving member (4) is connected between the output end of the first driving member (2) and the sample stage (1), and the third driving member (4) is used to drive the sample stage (1) to move in a vertical direction.

3. A PID-controlled sample temperature adjustment platform according to claim 1, characterized in that: A fourth driving member (5) and a fifth driving member (6) are connected between the sample stage (1) and the first driving member (2); the sample stage (1) is connected to the output end of the fifth driving member (6); the output end of the fifth driving member (6) is rotatable, and the rotation axis is arranged in the horizontal direction; the fifth driving member (6) is connected to the output end of the fourth driving member (5); the output end of the fourth driving member (5) is rotatable, and the rotation axis of the output end of the fourth driving member (5) is arranged in the horizontal direction and is perpendicular to the rotation axis direction of the output end of the fifth driving member (6).

4. A PID-controlled sample temperature adjustment platform according to claim 1, characterized in that: The sample stage (1) is provided with a plurality of positioning holes (7), and positioning components (8) are provided corresponding to the positioning holes (7). The positioning component (8) comprises a suction head (81) and a sixth driving member (82). The output end of the suction head (81) is connected to the positioning hole (7), and the input end of the suction head (81) is connected to the output end of the sixth driving member (82). The sixth driving member (82) is used to drive the suction head (81) to fix the sample.

5. The PID-controlled sample temperature adjustment platform according to claim 1, characterized in that: The sample stage (1) comprises a base (12) and a storage table (11), the storage table (11) is mounted on the base (12), the output end of the second driving member (3) is connected to the base (12), the PID temperature controller comprises a heating part (9), a heat conducting plate (91) is connected between the heating part (9) and the base (12), and the heat conducting plate (91) is in contact with the storage table (11).

6. A PID-controlled sample temperature adjustment platform according to claim 5, characterized in that: It comprises a heat insulation component (10), wherein the heat insulation component (10) comprises a first heat insulation part (101), and the first heat insulation part (101) is respectively connected to the base (12) and the storage table (11).

7. A PID-controlled sample temperature adjustment platform according to claim 6, characterized in that: The thermal insulation component (10) comprises a first positioning portion (102) and a second positioning portion (103) which are parallel to each other. The first positioning portion (102) is arranged inside the first thermal insulation portion (101), and the second positioning portion (103) is arranged outside the first thermal insulation portion (101). The storage table (11) is located inside the first thermal insulation portion (101) and abuts against the first positioning portion (102). The base (12) is sleeved on the outside of the first thermal insulation portion (101) and abuts against the second positioning portion (103).

8. A PID-controlled sample temperature adjustment platform according to claim 7, characterized in that: The heat insulation component (10) comprises a second heat insulation part (104), the second heat insulation part (104) being threadedly connected to the base (12); when the second heat insulation part (104) is connected to the base (12), the second heat insulation part (104) and the first positioning part (102) are pressed together against the storage table (11).

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