Wafer bearing device and semiconductor detection equipment

Abstract

The utility model provides a wafer bearing device and semiconductor detection equipment. The wafer bearing device comprises a wafer bearing table and an electric field forming piece, the wafer bearing table is used for bearing a wafer to be detected; the electric field forming piece is arranged outside the wafer bearing table in a surrounding mode, and the electric field forming piece forms an electric field which is distributed in a radial mode in the radius direction of the wafer bearing table. The direction of the electric field is set from the electric field forming piece to the circle center of the wafer bearing table or from the circle center of the wafer bearing table to the electric field forming piece, the to-be-detected wafer is located in the electric field forming piece, and the electric field forming piece utilizes the electric field force of the electric field to electric charges. And returning at least part of the charges deviating from the edge of the to-be-detected wafer to the surface of the to-be-detected wafer. According to the utility model, the problem that the measured data is abnormal due to electric leakage caused by charge loss when charges excited by the corona gun hit the edge of the wafer is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductors, and in particular to a wafer carrying device and semiconductor testing equipment. Background Art

[0002] In the semiconductor manufacturing process, a measuring machine is needed to detect the equivalent capacitance thickness (CET), surface damage (PDM), surface barrier voltage (VSB), surface interface state density (LI) and other related parameters of the wafer through the capacitance-voltage characteristic curve, namely the CV characteristic curve, so as to characterize the quality of the wafer surface film, namely the dielectric layer. The wafer detector (Semiconductor Diagnost ics Inc, SDI) uses a corona gun to excite the charge on the surface of the wafer, namely the dielectric layer, and uses a non-contact vibration probe to measure the surface voltage, and makes a CV characteristic curve to analyze the quality of the wafer surface film.

[0003] In the actual measurement process of SDI, Figure 1 and Figure 2 As shown, the charges 11 excited by the corona gun 10 will hit the surface of the wafer 13 placed on the carrier 12, but part of the charges 11 at the edge 14 of the wafer will be offset, causing the charges 11 to appear outside the wafer edge 14. The loss of the charges 11 at the edge 14 of the wafer is prone to leakage, resulting in abnormal measurement data.

[0004] Therefore, it is necessary to provide a new type of wafer carrier and semiconductor testing equipment to solve the above problems existing in the prior art. Utility Model Content

[0005] The utility model aims to provide a wafer carrier and a semiconductor testing device to solve the problem in the prior art that the charge stimulated by the corona gun is easily lost when hitting the edge of the wafer, causing leakage and resulting in abnormal measurement data.

[0006] To achieve the above-mentioned purpose, the wafer supporting device of the utility model includes a wafer supporting platform and an electric field forming member; the wafer supporting platform is used to support the wafer to be detected; the electric field forming member is arranged outside the wafer supporting platform, and the electric field forming member forms an electric field along the radius direction of the wafer supporting platform and is radially distributed, and the direction of the electric field is set from the electric field forming member to the center of the wafer supporting platform or from the center of the wafer supporting platform to the electric field forming member, and the wafer to be detected is located in the electric field forming member, and the electric field forming member uses the electric field force of the electric field on the charge to return at least part of the charge offset outside the edge of the wafer to be detected to the surface of the wafer to be detected.

[0007] The beneficial effect of the wafer carrying device of the utility model is that the electric field forming member is surrounded by the wafer carrying platform, and the electric field forming member forms an electric field along the radius direction of the wafer carrying platform and distributed radially, the direction of the electric field is set from the electric field forming member to the center of the wafer carrying platform or from the center of the wafer carrying platform to the electric field forming member, the wafer to be detected is located in the electric field forming member, and the electric field forming member uses the electric field force of the electric field on the charge to return at least part of the charge offset outside the edge of the wafer to be detected to the surface of the wafer to be detected, that is, an external electric field is introduced by setting the electric field forming member, and the direction of the charge offset outside the edge of the wafer to be detected is corrected by the electric field so that it can return to the surface of the wafer to be detected, thereby reducing the charge loss at the edge of the wafer to be detected, increasing the charge amount on the surface of the wafer to be detected, improving the accuracy of detection, and solving the problem of leakage caused by the charge loss at the edge of the wafer to be detected when the corona discharge unit hits the edge of the wafer to be detected, resulting in abnormal measurement data.

[0008] Preferably, the electric field forming member is an annular structure, and the electric field forming member is arranged concentrically with the wafer carrier. Its beneficial effect is: to ensure that each area of ​​the edge of the wafer to be tested has the same electric field strength, so that the electric field can drive the charges outside the edge of the wafer to be tested to return to the surface of the wafer to be tested, thereby reducing the charge loss at the edge of the wafer to be tested, increasing the charge amount on the surface of the wafer to be tested, and improving the accuracy of detection.

[0009] Preferably, the electric field forming member is connected to a device that provides a positive voltage to form an electric field set by the electric field forming member pointing to the center of the wafer carrier, so that at least part of the positive charges offset outside the edge of the wafer to be detected are returned to the surface of the wafer to be detected. The beneficial effect is to ensure that the positive charges outside the edge of the wafer to be detected can be returned to the surface of the wafer to be detected.

[0010] Preferably, the electric field forming member is connected to a device providing a negative voltage to form an electric field set by the center of the wafer carrier pointing to the electric field forming member, so that at least part of the negative charges offset outside the edge of the wafer to be detected are returned to the surface of the wafer to be detected. The beneficial effect is to ensure that the negative charges outside the edge of the wafer to be detected can be returned to the surface of the wafer to be detected.

[0011] Preferably, the wafer carrying device further comprises a base, the wafer carrying platform and the electric field forming member are spaced apart on the base, and an insulating member is provided between the electric field forming member and the wafer carrying platform to insulate the electric field forming member from the wafer carrying platform. The beneficial effect is that the electric field forming member and the wafer carrying platform are insulated and non-conductive, thereby forming an electric field in the annular area surrounded by the electric field forming member.

[0012] Preferably, the top surface of the electric field forming member is not higher than the top surface of the wafer to be tested placed on the wafer supporting platform. The beneficial effect is to avoid the interference of the electric field forming member on the placement of the wafer to be tested on the wafer supporting platform.

[0013] Preferably, when the wafer carrying device is placed horizontally, the electric field forming member forms a projection ring on the surface of the base, and the distance between the edge of the inner circle of the projection ring and the edge of the wafer carrying platform is not less than 2 cm. The beneficial effect is to avoid the interference of the electric field forming member on the placement of the wafer to be tested on the wafer carrying platform.

[0014] Preferably, the wafer carrying device further comprises a movable adjusting member, the two ends of which are respectively connected to the electric field forming member and the base, and the movable adjusting member moves relative to the base to adjust the direction of the electric field formed by the electric field forming member. Its beneficial effect is that the movable adjusting member moves relative to the base to adjust the orientation of the electric field forming member, thereby achieving the purpose of adjusting the height of the electric field forming member and the direction of the electric field formed by the electric field forming member, which is conducive to returning the charges offset outside the edge of the wafer to be detected to the surface of the wafer to be detected, thereby reducing the charge loss at the edge of the wafer to be detected, increasing the amount of charge on the surface of the wafer to be detected, and improving the accuracy of detection.

[0015] Preferably, the electric field forming member is a metal member, a metal alloy member or a composite metal member. The beneficial effect is that the electric field forming member is connected to a positive voltage or a negative voltage to form an electric field.

[0016] Preferably, the semiconductor detection equipment includes the wafer carrying device, a corona discharge unit, a charge detection unit and a processing unit; the corona discharge unit is used to perform corona spraying on the surface of the wafer to be detected; the charge detection unit is used to detect the charge amount of positive ions or negative ions deposited on the surface of the wafer to be detected; the processing unit is connected to the charge detection unit, and the processing unit is used to produce a CV characteristic curve according to the charge amount and analyze the quality of the surface film of the wafer to be detected.

[0017] The beneficial effect of the semiconductor detection equipment of the utility model lies in that: by setting the wafer supporting device, the wafer to be detected is located in the electric field forming member, and the electric field forming member uses the electric field force of the electric field on the charge to return at least part of the charge offset outside the edge of the wafer to be detected to the surface of the wafer to be detected, that is, an external electric field is introduced by setting the electric field forming member, and the direction of the charge offset outside the edge of the wafer to be detected is corrected by the electric field so that it can return to the surface of the wafer to be detected, thereby reducing the charge loss at the edge of the wafer to be detected and increasing the charge amount on the surface of the wafer to be detected, which is conducive to drawing a high-precision CV characteristic curve and improving the accuracy of the quality measurement of the surface film of the wafer to be detected. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A side view schematic diagram showing that charges excited by a corona gun in the prior art are offset at the edge of a wafer;

[0019] Figure 2 for Figure 1 A schematic top view showing that the charges excited by the corona gun are deflected at the edge of the wafer;

[0020] Figure 3 It is a side view schematic diagram of a wafer carrying device in the first embodiment of the utility model;

[0021] Figure 4 for Figure 3 A schematic top view of the middle electric field forming member disposed on the top surface of the base;

[0022] Figure 5 for Figure 3 A schematic diagram of the force direction of the electric charges in the electric field formed by the electric field forming member in the wafer supporting device shown;

[0023] Figure 6 for Figure 3 A schematic top view of the wafer carrier showing the return of charges to the edge of the wafer to be inspected;

[0024] Figure 7 It is a side view schematic diagram of a wafer carrying device in a second embodiment of the utility model;

[0025] in, Figures 1 to 7 The reference numerals in the figures are respectively:

[0026] 10. Corona gun; 11. Electric charge; 12. Carrier; 13. Wafer; 14. Wafer edge;

[0027] 100. Wafer carrier; 200. Wafer to be inspected; 210. Edge; 300. Electric field forming member; 400. Base; 500. Movable adjustment member. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the utility model belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0029] In order to overcome the problems existing in the prior art, the embodiments of the utility model provide a wafer carrier and a semiconductor detection device to solve the problem in the prior art that the charge stimulated by the corona gun is easily lost when it hits the edge of the wafer, causing leakage, resulting in abnormal measurement data.

[0030] Figure 3 It is a side view schematic diagram of a wafer carrying device in the first embodiment of the utility model; Figure 4 for Figure 3 A schematic top view of the middle electric field forming member disposed on the top surface of the base; Figure 5 for Figure 3 A schematic diagram of the force direction of the electric charges in the electric field formed by the electric field forming member in the wafer supporting device shown; Figure 6 for Figure 3 A schematic top view of the wafer carrier showing the return of charges to the edge of the wafer to be inspected.

[0031] In some embodiments of the present invention, reference Figures 3 to 6 The wafer carrying device includes a wafer carrying platform 100 and an electric field forming member 300; the wafer carrying platform 100 is used to carry a wafer 200 to be detected; the electric field forming member 300 is arranged outside the wafer carrying platform 100, and the electric field forming member 300 forms an electric field along the radius of the wafer carrying platform 100 and is radially distributed, and the direction of the electric field is set from the electric field forming member 300 to the center of the wafer carrying platform 100 or from the center of the wafer carrying platform 100 to the electric field forming member 300, and the wafer 200 to be detected is located in the electric field forming member 300, and the electric field forming member 300 uses the electric field force of the electric field on the charge 11 to return at least part of the charge 11 offset outside the edge 210 of the wafer 200 to the surface of the wafer 200 to be detected.

[0032] Specifically, the electric field forming member 300 is arranged outside the wafer carrier 100, and the electric field forming member 300 forms an electric field along the radius direction of the wafer carrier 100 and is radially distributed. The direction of the electric field is set from the electric field forming member 300 to the center of the wafer carrier 100 or from the center of the wafer carrier 100 to the electric field forming member 300. The wafer 200 to be detected is located in the electric field forming member 300. The electric field forming member 300 uses the electric field force of the electric field on the charge 11 to return at least part of the charge 11 offset outside the edge 210 of the wafer 200 to be detected to the surface of the wafer 200 to be detected, that is, an external electric field is introduced by setting the electric field forming member 300, and the direction of the charge 11 offset outside the edge 210 of the wafer 200 to be detected is corrected by the electric field so that it can return to the surface of the wafer 200 to be detected, such as Figure 5 and Figure 6 As shown, the loss of charge 11 at the edge 210 of the wafer 200 to be detected is reduced, the amount of charge on the surface of the wafer 200 to be detected is increased, the accuracy of detection is improved, and the problem of leakage caused by the loss of charge 11 at the edge 210 of the wafer 200 to be detected caused by the corona discharge unit hitting the edge 210 of the wafer 200 to be detected, resulting in abnormal measurement data, is solved.

[0033] In some embodiments of the present invention, reference Figures 3 to 6 The wafer carrying device also includes a base 400, the wafer carrying platform 100 and the electric field forming element 300 are spaced apart on the base 400, and an insulating element (not shown in the figure) is provided between the electric field forming element 300 and the wafer carrying platform 100 to insulate the electric field forming element 300 from the wafer carrying platform 100, so that the electric field forming element 300 and the wafer carrying platform 100 are insulated and non-conductive, thereby forming an electric field in the annular area surrounded by the electric field forming element 300.

[0034] In some embodiments of the present invention, reference Figures 3 to 6 The electric field forming element 300 is a ring structure, and the electric field forming element 300 is arranged cocentrically with the wafer carrier 100 to ensure that each area of ​​the edge 210 of the wafer 200 to be tested has the same electric field strength, so that the electric field can drive the charges outside the edge 210 of the wafer 200 to be tested to return to the surface of the wafer 200 to be tested, thereby reducing the charge loss at the edge 210 of the wafer 200 to be tested, increasing the charge amount on the surface of the wafer 200 to be tested, and improving the accuracy of detection.

[0035] In some embodiments of the utility model, the electric field forming element is connected to a device that provides a positive voltage to form an electric field set by the electric field forming element and directed toward the center of the wafer carrier, so that at least part of the positive charge offset outside the edge of the wafer to be inspected is returned to the surface of the wafer to be inspected, thereby ensuring that the positive charge outside the edge of the wafer to be inspected can be returned to the surface of the wafer to be inspected.

[0036] In some other embodiments of the utility model, the electric field forming element is connected to a device that provides a negative voltage to form an electric field set by the center of the wafer supporting platform pointing to the electric field forming element, so that at least part of the negative charge offset outside the edge of the wafer to be inspected is returned to the surface of the wafer to be inspected, thereby ensuring that the negative charge outside the edge of the wafer to be inspected can be returned to the surface of the wafer to be inspected.

[0037] In the embodiment of the utility model, the direction of force on positive charges in the electric field is the same as the direction of the field strength, and the direction of force on negative charges in the electric field is opposite to the direction of the field strength. The force on the charge in the electric field is calculated according to Coulomb's theorem, and the force F=Eq (E is the electric field strength, q is the charge of the charge).

[0038] In some specific embodiments of the present invention, the electric field forming element is also connected to a grounding wire.

[0039] In some embodiments of the present invention, reference Figure 3 The top surface of the electric field forming member 300 is not higher than the top surface of the wafer 200 to be inspected carried on the wafer supporting platform 100 to avoid the electric field forming member 300 interfering with the placement of the wafer 200 to be inspected on the wafer supporting platform 100 .

[0040] In some specific embodiments of the present invention, the top surface of the electric field forming element 300 is arranged flush with the top surface of the wafer to be detected 200 carried on the wafer supporting platform 100 to ensure that the charges outside the edge of the wafer to be detected can be returned to the surface of the wafer to be detected.

[0041] In some embodiments of the present invention, reference Figures 3 to 6 When the wafer supporting device is placed horizontally, the electric field forming element 300 forms a projection ring on the surface of the base 400, and the distance between the edge of the inner circle of the projection ring and the edge of the wafer supporting platform 100 is not less than 2 cm, so as to avoid the electric field forming element 300 interfering with the placement of the wafer 200 to be inspected on the wafer supporting platform 100.

[0042] Figure 7 It is a side view schematic diagram of a wafer carrying device in a second embodiment of the present invention.

[0043] In some embodiments of the present invention, reference Figure 7 The wafer carrying device further includes a movable adjusting member 500, the two ends of which are connected to the electric field forming member 300 and the base 400 respectively, and the movable adjusting member 500 moves relative to the base 400 to adjust the direction of the electric field formed by the electric field forming member 300. That is, the movable adjusting member 500 moves relative to the base 400 to adjust the direction of the electric field forming member 300, thereby achieving the purpose of adjusting the height of the electric field forming member 300 and the direction of the electric field formed by the electric field forming member 300, which is conducive to returning the charges offset outside the edge of the wafer 200 to be detected to the surface of the wafer 200 to be detected, thereby reducing the charge loss at the edge of the wafer 200 to be detected, increasing the charge amount on the surface of the wafer 200 to be detected, and improving the accuracy of detection.

[0044] Specifically, when the electric field formed by the electric field forming element 300 is perpendicular to the base 400, it cannot effectively return the charges offset from the edge 210 of the wafer 200 to the surface of the wafer 200 to be detected. At this time, the movable adjustment element 500 can be moved relative to the base 400 to adjust the orientation of the electric field forming element 300 so that the electric field forming element 300 is tilted relative to the base 400. The specific tilt angle of the electric field forming element 300 is based on the electric field formed by the electric field forming element 300, which can enable the charges offset from the edge 210 of the wafer 200 to be detected to be returned to the surface of the wafer 200 to be detected, and the electric field forming element 300 does not interfere with the placement of the wafer 200 to be detected on the wafer carrier 100.

[0045] In some embodiments of the present invention, reference Figure 7 The movable adjusting member 500 is a hinge, which has a simple structure and is easy to operate.

[0046] In some embodiments of the utility model, the electric field forming component is a metal component, a metal alloy component or a composite metal component, that is, the electric field forming component is made of conductive metal, metal alloy or composite metal material, so that the electric field forming component is connected to positive voltage or negative pressure to form an electric field.

[0047] In some embodiments of the utility model, the semiconductor detection equipment includes the wafer carrying device, the corona discharge unit, the charge detection unit and the processing unit; the corona discharge unit is used to perform corona spraying on the surface of the wafer to be detected; the charge detection unit is used to detect the charge amount of positive ions or negative ions deposited on the surface of the wafer to be detected; the processing unit is connected to the charge detection unit, and the processing unit is used to produce a CV characteristic curve according to the charge amount and analyze the quality of the surface film of the wafer to be detected.

[0048] Specifically, the wafer supporting device is arranged so that the wafer to be detected is located in the electric field forming element, and the electric field forming element uses the electric field force of the electric field on the charge to return at least part of the charge offset outside the edge of the wafer to be detected to the surface of the wafer to be detected, that is, an external electric field is introduced by arranging the electric field forming element, and the direction of the charge offset outside the edge of the wafer to be detected is corrected by the electric field so that it can return to the surface of the wafer to be detected, thereby reducing the charge loss at the edge of the wafer to be detected and increasing the charge amount on the surface of the wafer to be detected, which is conducive to drawing a high-precision CV characteristic curve and improving the accuracy of the quality measurement of the surface film of the wafer to be detected.

[0049] In the embodiment of the utility model, the corona discharge unit selects the charge according to the properties of the wafer. For N-type semiconductors, the corona discharge unit excites positive charges, and for P-type semiconductors, the corona discharge unit excites negative charges.

[0050] In some specific embodiments of the present invention, the corona discharge unit comprises:

[0051] A corona gun, wherein the corona gun has a needle-shaped corona electrode, and the needle-shaped corona electrode discharges to ionize the air around the wafer to be detected to form positive and negative ions, and the positive ions or negative ions are deposited on the surface of the wafer to be detected;

[0052] The corona driving unit is used to apply voltage to the needle-shaped corona electrode for discharge.

[0053] In some specific embodiments of the present invention, the charge detection unit includes:

[0054] A sensor, used to obtain instantaneous displacement current information of the surface of the wafer to be detected;

[0055] The detection unit is used to detect the charge amount of the positive ions or negative ions deposited on the surface of the wafer to be detected according to the instantaneous displacement current information obtained by the sensor.

[0056] In some specific embodiments of the present invention, the sensor is located on the wafer supporting platform.

[0057] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A wafer carrying device, characterized in that: include: A wafer carrier, used for carrying wafers to be inspected; An electric field forming member is arranged outside the wafer supporting platform, and the electric field forming member forms an electric field that is radially distributed along the radius of the wafer supporting platform. The direction of the electric field is set from the electric field forming member to the center of the wafer supporting platform or from the center of the wafer supporting platform to the electric field forming member. The wafer to be detected is located in the electric field forming member. The electric field forming member uses the electric field force of the electric field on the charge to return at least part of the charge offset outside the edge of the wafer to be detected to the surface of the wafer to be detected.

2. The wafer carrier device according to claim 1, characterized in that: The electric field forming member is a ring structure, and the electric field forming member is arranged cocentrically with the wafer supporting platform.

3. The wafer carrier device according to claim 1, characterized in that: The electric field forming element is connected to a device that provides a positive voltage to form an electric field set by the electric field forming element toward the center of the wafer carrier, so that at least part of the positive charge offset outside the edge of the wafer to be inspected is returned to the surface of the wafer to be inspected.

4. The wafer carrier device according to claim 1, characterized in that: The electric field forming element is connected to a device that provides a negative voltage to form an electric field set by the center of the wafer supporting platform pointing to the electric field forming element, so that at least part of the negative charge offset outside the edge of the wafer to be inspected returns to the surface of the wafer to be inspected.

5. The wafer carrier device according to claim 1, characterized in that: It also includes a base, the wafer carrying platform and the electric field forming member are spaced apart on the base, and an insulating member is arranged between the electric field forming member and the wafer carrying platform to insulate the electric field forming member from the wafer carrying platform.

6. The wafer carrying device according to claim 1, characterized in that: The top surface of the electric field forming member is not higher than the top surface of the wafer to be inspected carried on the wafer carrying platform.

7. The wafer carrying device according to claim 5, characterized in that: When the wafer carrying device is placed horizontally, the electric field forming member forms a projection ring on the surface of the base, and the distance between the edge of the inner circle of the projection ring and the edge of the wafer carrying platform is not less than 2 cm.

8. The wafer carrying device according to claim 5, characterized in that: It also includes a movable adjusting member, two ends of which are respectively connected to the electric field forming member and the base, and the movable adjusting member moves relative to the base to adjust the direction of the electric field formed by the electric field forming member.

9. The wafer carrying device according to claim 1, characterized in that: The electric field forming member is a metal member.

10. A semiconductor testing device, characterized in that: include: The wafer carrier device according to any one of claims 1 to 9; A corona discharge unit is used to perform corona discharge on the surface of the wafer to be inspected; A charge detection unit, used to detect the charge amount of positive ions or negative ions deposited on the surface of the wafer to be detected; A processing unit is connected to the charge detection unit, and is used to make a CV characteristic curve according to the charge amount and analyze the quality of the surface film of the wafer to be detected.

Images