Inspection Equipment

Abstract

An inspection device (10) comprises: a conductive member (310) having a ground surface (312); an insulation member (320) at least a part of which faces the ground surface (312); and an antenna element (330) provided on a surface of the insulation member (320), the surface facing the ground surface (312).

Description

[Technical field]

[0001] The present invention relates to an inspection device. [Background technology]

[0002] In recent years, various inspection devices have been developed for inspecting semiconductor devices having antennas. For example, an inspection device as described in Patent Document 1 includes a holding section for holding a semiconductor device, which is a device under test (DUT), and an antenna section for inspecting the DUT. The antenna section performs an OTA (Over-the-Air) inspection of the DUT. The antenna section includes an insulating substrate. An antenna element is provided on the lower surface side of the insulating substrate. A ground pattern is provided on the upper surface side of the insulating substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-27777 A Summary of the Invention [Problem to be solved by the invention]

[0004] When an antenna element and a conductive member such as a ground pattern face each other via an insulating member such as an insulating substrate, the surface of the antenna element facing the conductive member is bonded to the insulating member. In order to bond the surface of the antenna element to the insulating member, the surface of the antenna element may be roughened. In this case, the antenna gain may be reduced.

[0005] One example of an object of the present invention is to suppress a decrease in antenna gain. Other objects of the present invention will become apparent from the description of this specification. [Means for solving the problem]

[0006] One aspect of the present invention is a conductive member having a ground plane; an insulating member having at least a portion facing the ground plane; an antenna element provided on a surface of the insulating member facing the ground surface; The inspection device includes: Effect of the Invention

[0007] According to the above aspect of the present invention, it is possible to suppress a decrease in antenna gain. [Brief description of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view of an inspection device according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of an antenna unit according to the embodiment. [Diagram 3] 1 is a perspective view of a top surface of a semiconductor device; [Figure 4] 4 is a graph showing an example of the relationship between the distance between the antenna element and the ground plane and the radiation efficiency of the antenna unit. [Diagram 5] FIG. 11 is a cross-sectional view of an antenna unit according to a comparative example. [Figure 6] 5A and 5B are diagrams illustrating a radiation pattern of radio waves from an antenna unit according to an embodiment and a radiation pattern of radio waves from an antenna unit according to a comparative example. [Figure 7] 11 is a graph showing frequency characteristics of boresight gain of an antenna unit according to an embodiment and frequency characteristics of boresight gain of an antenna unit according to a comparative example. [Figure 8] 11 is a cross-sectional view of an antenna unit according to a first modified example. FIG. [Figure 9] FIG. 11 is a cross-sectional view of an inspection device according to a second modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, embodiments and modifications of the present invention will be described with reference to the drawings. In all the drawings, similar components are denoted by similar reference numerals, and the description thereof will be omitted as appropriate.

[0010] In this specification, ordinal numbers such as "first," "second," "third," etc., unless otherwise specified, are used merely to distinguish between similarly named configurations and do not imply any particular characteristics (e.g., order or importance) of the configurations.

[0011] Fig. 1 is a cross-sectional view of an inspection device 10 according to an embodiment. Fig. 2 is a perspective view of an antenna unit 30 according to an embodiment. Fig. 3 is a perspective view of the top surface of a semiconductor device 500.

[0012] 1 to 3, the direction of the arrow indicating the first direction X, the second direction Y, or the third direction Z indicates the positive direction of the direction indicated by the arrow. On the other hand, the opposite direction of the arrow indicating the first direction X, the second direction Y, or the third direction Z indicates the negative direction of the direction indicated by the arrow. Also, the white circle with X indicating the second direction Y indicates that the positive direction of the direction indicated by the white circle with X is the direction from the front to the back of the paper, and the negative direction of the direction indicated by the white circle with X is the direction from the back to the front of the paper. The same applies to Figs. 5, 6, 8, and 9 described later.

[0013] The first direction X is a direction parallel to the horizontal direction, i.e., a direction perpendicular to the vertical direction. Specifically, the first direction X is a direction parallel to one side of the substantially square semiconductor device 500 described later. The second direction Y is a direction parallel to the horizontal direction and perpendicular to the first direction X. Specifically, the second direction Y is a direction parallel to another side perpendicular to the side parallel to the first direction X of the semiconductor device 500. The third direction Z is a vertical direction and perpendicular to both the first direction X and the second direction Y. The positive direction of the third direction Z is the upward direction in the vertical direction. The negative direction of the third direction Z is the downward direction in the vertical direction.

[0014] 1 is a cross section passing through the center of the inspection device 10 in the second direction Y along a direction perpendicular to the second direction Y. In FIG.

[0015] First, a semiconductor device 500 that is a device under test (DUT) of the testing apparatus 10 will be described with reference to FIG.

[0016] Four antenna elements 510 are provided on the upper surface of the semiconductor device 500. The outer shape of the antenna elements 510 is a plate-like square, but may be a plate-like circular shape or any other shape. The four antenna elements 510 are arranged in a square lattice of two rows and two columns so as to form an array antenna. By controlling the conditions such as the amplitude and phase of the radio wave radiated from each antenna element 510, the radio wave radiated from the semiconductor device 500 can be controlled. The layout of the antenna elements 510 is not limited to the layout according to this embodiment. For example, only one antenna element 510 may be provided on the upper surface of the semiconductor device 500. Also, multiple antenna elements 510 may be arranged in a rectangular lattice. Also, multiple antenna elements 510 may be arranged in a row in one direction. Alternatively, multiple antenna elements 510 may be arranged in a polygonal lattice such as a triangular lattice, a rectangular lattice, or a hexagonal lattice. Alternatively, multiple antenna elements 510 may be arranged in a circular ring or an elliptical ring.

[0017] Next, the inspection device 10 will be described with reference to FIGS.

[0018] The inspection device 10 includes a holding section 20 and an antenna section 30. The holding section 20 holds a semiconductor device 500. The holding section 20 has an inspection board 110, a socket 120, and a fixing section 200. The antenna section 30 inspects the semiconductor device 500.

[0019] The inspection board 110 is, for example, a PCB (Printed Circuit Board). The socket 120 is provided on the upper surface of the inspection board 110. The semiconductor device 500 is mounted on the upper surface of the inspection board 110 via the socket 120. The inspection board 110 and the semiconductor device 500 are electrically connected to each other via the socket 120. A signal input to the inspection board 110 is input to the semiconductor device 500 via the socket 120. Also, a signal output from the semiconductor device 500 is output from the inspection board 110 via the socket 120.

[0020] The fixing part 200 is formed of an insulating material such as resin. The fixing part 200 holds (fixes) the semiconductor device 500 toward the inspection device 10. Specifically, the fixing part 200 has a pressing part 202 that contacts the edge of the upper surface of the semiconductor device 500. By bringing the pressing part 202 into contact with the edge of the upper surface of the semiconductor device 500, the fixing part 200 fixes the semiconductor device 500 in a predetermined position on the socket 120 and presses the semiconductor device 500 toward the socket 120. This ensures contact between the semiconductor device 500 and the socket 120.

[0021] The fixing portion 200 defines a hole 210 that exposes at least a portion of the semiconductor device 500, specifically at least a portion of the top surface of the semiconductor device 500. Radio waves radiated from an antenna element 510 provided on the top surface of the semiconductor device 500 reach the antenna unit 30 via the hole 210. In addition, radio waves radiated from the antenna unit 30 reach the antenna element 510 provided on the top surface of the semiconductor device 500 via the hole 210.

[0022] The antenna section 30 performs an OTA (Over-the-Air) inspection of the semiconductor device 500. The antenna section 30 is disposed above the semiconductor device 500. The antenna section 30 performs at least one of transmitting radio waves to be radiated to the semiconductor device 500 and receiving radio waves radiated from the semiconductor device 500. Specifically, the antenna section 30 is electrically connected to an external measuring device (not shown). Based on a signal input from the external measuring device to the antenna section 30, radio waves are radiated from the antenna section 30 toward the semiconductor device 500. Also, based on the radio waves radiated from the semiconductor device 500 toward the antenna section 30, a signal is output from the antenna section 30 to the external measuring device.

[0023] Next, the antenna unit 30 will be described in detail with reference to FIGS.

[0024] The antenna section 30 includes a conductive member 310 , an insulating member 320 , an antenna element 330 , a first stripline 342 , a second stripline 344 , a first via 352 and a second via 354 .

[0025] The conductive member 310 is a conductive plate made of a metal such as aluminum. When viewed in the vertical direction, the conductive member 310 is substantially square. The shape of the conductive member 310 is not limited to the shape according to this embodiment. When viewed in the vertical direction, the conductive member 310 may be, for example, a quadrangle other than a square, such as a substantially rectangular shape.

[0026] A recess 314 that opens downward from the conductive member 310 is provided on the lower surface of the conductive member 310. The bottom surface of the recess 314 serves as a ground surface 312. The recess 314 is formed by, for example, cutting. In this case, the number of components of the antenna unit 30 can be reduced compared to a case in which the ground surface 312A and the antenna element 330 are separated from each other by a spacer 360A disposed between the conductive member 310A and the insulating member 320 as shown in FIG. 8, which will be described later.

[0027] The insulating member 320 is, for example, a resin substrate. The insulating member 320 is fixed to the conductive member 310 by, for example, a screw that penetrates the insulating member 320 from the lower surface of the insulating member 320, and the lower surface of the conductive member 310 and the upper surface of the insulating member 320 are in contact with each other. As a result, at least a part of the insulating member 320, specifically, the part of the upper surface of the insulating member 320 covered by the concave portion 314 of the conductive member 310 faces the ground plane 312 of the conductive member 310. Further, a conductive pattern formed of copper foil may be provided on the portion of the upper surface side of the insulating member 320 that is in contact with the conductive member 310.

[0028] The antenna element 330 is provided on the upper surface of the insulating member 320. The antenna element 330 is, for example, a conductive pattern formed of metal. The antenna element 330 may be a sheet metal. The antenna element 330 is provided on the surface side of the insulating member 320 that faces the ground plane 312 of the conductive member 310. Further, the antenna element 330 and the ground plane 312 face each other via a space (a region where air exists).

[0029] When viewed in the direction from the antenna element 330 toward the ground plane 312, that is, in the positive direction of the third direction Z, the shape of the space between the insulating member 320 and the ground plane 312, that is, the shape of the concave portion 314, is, for example, substantially similar to the shape of the antenna element 330. Note that the shape of the concave portion 314 may be a shape different from the similar shape of the antenna element 330.

[0030] Next, an example of the details of the antenna element 330 will be described. The length L of one side of the antenna element 330 can be, for example, 1 / 3λ0 < L < 1 / 2λ0, where λ0 is the wavelength in free space. The resonance frequency f of the antenna element 330 can be calculated by the following formula 1.

Equation

number

number

[0031] Moreover, the radiation efficiency η of the antenna unit 30 can be expressed by the following formula 4.

number

number

number

number

[0032] Fig. 4 is a graph showing an example of the relationship between the distance between antenna element 330 and ground plane 312 and the radiation efficiency of antenna unit 30. In Fig. 4, the horizontal axis of the graph indicates the distance between antenna element 330 and ground plane 312, and the vertical axis of the graph indicates the radiation efficiency of antenna unit 30. The relationship shown in Fig. 4 is calculated from Equation 4.

[0033] In one example, the distance between the antenna element 330 and the ground surface 312 is determined by the radiation efficiency η of Equation 4. As shown in FIG. 4, the radiation efficiency of the antenna unit 30 increases as the distance between the antenna element 330 and the ground surface 312 increases, and the change becomes gentle and saturated when the distance exceeds 0.2 mm. In the above example, the distance between the antenna element 330 and the ground surface 312 is set to 0.5 mm, which is a sufficiently large value for the radiation efficiency of the antenna unit 30 of 0.97 and does not vary significantly even if the distance varies. The distance between the antenna element 330 and the ground surface 312 may be 0.5 mm or less.

[0034] In one example, the region of the space between the insulating member 320 and the ground plane 312, i.e., the horizontal dimension of the recess 314, for example, the dimension in the first direction X or the dimension in the second direction Y, can be set to be equal to or less than twice the horizontal dimension of the antenna element 330, for example, the dimension in the first direction X or the dimension in the second direction Y. In this case, the inner wall of the recess 314 blocks the surface wave, so that the surface wave loss 1 / Q in the above-mentioned formula 4 swHowever, if the dimensions of the recess 314 are made too small, the inner wall of the recess 314 comes too close to the antenna element 330, causing effects such as the above formulas 1 to 7 for the antenna element 330 no longer being satisfied. For this reason, the dimensions of the recess 314 should be set so that the above formulas 1 to 7 are satisfied and the surface wave loss 1 / Q sw An appropriate value capable of suppressing is selected. The horizontal dimension of the recess 314 may be greater than twice the horizontal dimension of the antenna element 330.

[0035] Power is supplied to the antenna element 330 from a first stripline 342 provided on the lower surface side of the insulating member 320 through a first via 352 penetrating the insulating member 320. The first stripline 342 extends parallel to the first direction X. One end of the first stripline 342 is connected to the first via 352. Meanwhile, the other end of the first stripline 342 can be connected to an external measuring device (not shown). Power is supplied to the antenna element 330 from a second stripline 344 provided on the lower surface side of the insulating member 320 through a second via 354 penetrating the insulating member 320. The second stripline 344 extends parallel to the second direction Y. One end of the second stripline 344 is connected to the second via 354. The other end of the second stripline 344 can be connected to an external measuring device (not shown). The antenna unit 30 is capable of at least one of transmitting and receiving horizontally polarized waves and vertically polarized waves by two striplines, the first stripline 342 and the second stripline 344. The number of striplines provided in the antenna unit 30 may be only one. Furthermore, the method of feeding power to the antenna element 330 may be by non-contact electromagnetic coupling without using the first via 352 and the second via 354.

[0036] 5 is a cross-sectional view of an antenna unit 30K according to a comparative example. The antenna unit 30K according to the comparative example is similar to the antenna unit 30 according to the embodiment, except for the following points.

[0037] In the antenna unit 30K according to the comparative example, an insulating member 320K is provided on the lower surface side of a conductive member 310K. An antenna element 330K is provided on the lower surface side of the insulating member 320K.

[0038] A comparison between the antenna unit 30 according to the embodiment and an antenna unit 30K according to a comparative example will be described with reference to FIGS. 1, 2 and 5. FIG.

[0039] In the antenna section 30K according to the comparative example, the surface of the antenna element 330K facing the ground surface 312K is roughened in order to bond the antenna element 330K to the lower surface of the insulating member 320K. In this case, the conductor loss caused by the skin effect of the surface of the antenna element 330K facing the ground surface 312K is larger than when the surface of the antenna element 330K facing the ground surface 312K is not roughened. In contrast, in the antenna section 30 according to the embodiment, the surface of the antenna element 330 facing the ground surface 312 is not bonded to the surface of the insulating member 320. Therefore, the surface roughness of the surface of the antenna element 330 facing the ground surface 312 in the antenna section 30 according to the embodiment can be made smaller than the surface roughness of the surface of the antenna element 330K facing the ground surface 312K in the antenna section 30K according to the comparative example. The conductor loss of the antenna section is expressed by the reciprocal of Equation 6. If the surface roughness a is a variable in Equation 6, when there is no surface roughness, that is, when a = 0, the denominator of Equation 6 takes the minimum value and the Q value is maximized, and the conductor loss of the antenna part is 1 / Q c The opposite is true small Therefore, the conductor loss of the antenna unit 30 according to the embodiment can be made smaller than the conductor loss of the antenna unit 30K according to the comparative example. Therefore, in the embodiment, it is possible to suppress the decrease in antenna gain compared to the comparative example.

[0040] In the antenna unit 30K according to the comparative example, the insulating member 320 between the antenna element 330K and the ground surface 312K, i.e., the dielectric material, reduces the dielectric loss 1 / Q dIn contrast, the gap between the antenna element 330 and the ground plane 312 in the antenna unit 30 according to the embodiment is air. The dielectric loss is expressed by Q d The dielectric loss of the antenna unit 30 according to the embodiment is smaller than the dielectric loss of the antenna unit 30K according to the comparative example. Therefore, in the embodiment, the decrease in antenna gain can be suppressed compared to the comparative example.

[0041] Fig. 6 is a diagram showing a radiation pattern of radio waves from the antenna unit 30 according to the embodiment and a radiation pattern of radio waves from the antenna unit 30K according to the comparative example. In Fig. 6, the numbers on the outside of the circle with the scale indicate the azimuth of the radiation pattern (unit: degree). Also, the numbers written from the center of the circle to the 0 degree direction indicate the gain (unit: dBi). Also, the 0 degree direction of the radiation pattern, i.e., the boresight direction, is the negative direction of the third direction Z.

[0042] The boresight gain of the radiation pattern according to the embodiment is about 3 dB higher than the boresight gain of the radiation pattern according to the comparative example. As described above, this result suggests that the conductor loss and dielectric loss of the antenna unit 30 according to the embodiment are smaller than those of the antenna unit 30K according to the comparative example.

[0043] 7 is a graph showing frequency characteristics of the boresight gain of the antenna unit 30 according to the embodiment and the antenna unit 30K according to the comparative example. In FIG. 7, the vertical axis of the graph shows the gain at the boresight, and the horizontal axis of the graph shows the frequency.

[0044] The boresight gain of the embodiment is higher than that of the comparative example from 26 GHz to 31 GHz. This result suggests that the conductor loss and dielectric loss of the antenna unit 30 according to the embodiment are smaller than those of the antenna unit 30K according to the comparative example, and therefore the Q value of the antenna unit 30 according to the embodiment is higher than the Q value of the antenna unit 30K according to the comparative example. As a result, the usable frequency band of the antenna unit 30 according to the embodiment is wider than that of the antenna unit 30K according to the comparative example.

[0045] 8 is a cross-sectional view of an antenna unit 30A according to Modification 1. The antenna unit 30A according to this modification is similar to the antenna unit 30 according to the embodiment, except for the following points.

[0046] The lower surface of the conductive member 310A of the antenna unit 30A is flat. The insulating member 320 is connected to the lower surface of the conductive member 310A via a spacer 360A. The spacer 360A surrounds a partial area of ​​the lower surface of the conductive member 310A when viewed from below in the vertical direction. The area of ​​the lower surface of the conductive member 310A surrounded by the spacer 360A serves as a ground surface 312A. As a result, at least a portion of the insulating member 320 faces the ground surface 312A. The antenna element 330 is provided on the surface of the insulating member 320 facing the ground surface 312A.

[0047] In this modification, the distance in the third direction Z between the ground surface 312A and the insulating member 320 can be adjusted by adjusting the height of the spacer 360A in the third direction Z. In this case, it may be easier to adjust the distance between the ground surface 312A and the insulating member 320 compared to the case where the recess 314 is provided in the conductive member 310 as shown in FIG. 1. Also, in this modification, it is not necessary to form the recess 314 shown in FIG. 1 in the conductive member 310A, and the spacer 360A can be formed, for example, by simply punching a metal plate. In this case, the manufacturing cost of the antenna unit 30A can be reduced compared to the case where the recess 314 is provided in the conductive member 310 as shown in FIG. 1.

[0048] 9 is a cross-sectional view of an inspection device 10B according to Modification 2. The inspection device 10B according to this modification is similar to the inspection device 10 according to the embodiment, except for the following points.

[0049] The fixing portion 200B of the holding portion 20B has a pressing portion 202B that contacts the edge of the upper surface of the semiconductor device 500. The inner surface of the hole 210B of the fixing portion 200B has a staircase shape (a shape having steps) from the bottom to the opening of the hole 210B. In this case, it is possible to reduce distortion of the radiation pattern of radio waves from the semiconductor device 500 compared to the case where the inner surface of the hole 210B is flat in the third direction Z as shown in FIG.

[0050] Although the embodiment and modified examples of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0051] For example, in this embodiment, the antenna element 330 and the ground surface 312 face each other via air. However, a low-loss dielectric material may be provided between the antenna element 330 and the ground surface 312 instead of air. Even in this case, as shown in FIG. 5, the conductor loss and dielectric loss due to the skin effect on the surface of the antenna element 330 facing the ground surface 312 can be reduced compared to the case where the antenna element 330K is provided on the surface of the insulating member 320K opposite to the surface on which the conductive member 310K is located. Therefore, even in the antenna unit 30 in which a dielectric material is provided between the antenna element 330 and the ground surface 312, the decrease in antenna gain can be suppressed compared to the antenna unit 30K according to the comparative example.

[0052] According to the present specification, the following aspects are provided. (Aspect 1) Aspect 1 is a conductive member having a ground plane; an insulating member having at least a portion facing the ground plane; an antenna element provided on a surface of the insulating member facing the ground surface; The inspection device includes: According to the first aspect, unlike the case where an antenna element is provided on the surface of the insulating member opposite to the surface on which the conductive member is located, the antenna element is not bonded to the surface of the insulating member. Therefore, according to the first aspect, it is possible to reduce the conductor loss due to the skin effect of the surface of the antenna element facing the ground surface compared to the case where an antenna element is provided on the surface of the insulating member opposite to the surface on which the conductive member is located. Therefore, according to the first aspect, it is possible to suppress the decrease in antenna gain compared to the case where an antenna element is provided on the surface of the insulating member opposite to the surface on which the conductive member is located. (Aspect 2) Aspect 2 is 2. The inspection device according to claim 1, wherein the antenna element and the ground plane face each other via air. According to the second aspect, the dielectric constant and dielectric loss between the antenna element and the ground plane can be reduced compared to when the antenna element and the ground plane face each other via a dielectric material, and therefore, according to the second aspect, the decrease in antenna gain can be suppressed compared to when the antenna element and the ground plane face each other via a dielectric material. (Aspect 3) Aspect 3 is 3. The inspection device according to aspect 1 or 2, wherein the ground plane is a bottom surface of a recess provided in the conductive member. According to the third aspect, the number of parts in the antenna unit can be reduced compared to a case in which the ground plane and the antenna element are separated by a spacer disposed between the conductive member and the insulating member.

[0053] This application claims priority based on Japanese Patent Application No. 2020-143160, filed on August 27, 2020, the disclosure of which is incorporated herein in its entirety. [Explanation of symbols]

[0054] 10 Inspection equipment 10B Inspection equipment 20 Holding part 20B Holding part 30 Antenna section 30A Antenna section 30K Antenna section 110 Test board 120 Sockets 200 Fixed part 200B Fixed part 202 Clamp 202B Clamp 210 holes 210B hole 310 Conductive materials 310A Conductive material 310K Conductive material 312 Ground Plane 312A Ground Plane 312K Ground Plane 314 Recess 320 Insulating materials 320K Insulation material 330 Antenna Element 330K Antenna Element 342 1st Stripline 344 2nd Stripline 352 First Via 354 2nd Via 360A Spacer 500 Semiconductor device 510 Antenna Element X 1st direction Y Second direction Z 3rd direction

Claims

1. An inspection apparatus for inspecting a semiconductor device, comprising: a conductive member having a ground plane; an insulating member having at least a portion facing the ground plane; an antenna element provided on a surface of the insulating member facing the ground surface, the antenna element transmitting and receiving radio waves with the semiconductor device; An inspection device comprising:

2. 2. The inspection device according to claim 1, wherein the antenna element and the ground plane face each other via air.

3. 3. The inspection device according to claim 1, wherein the ground plane is a bottom surface of a recess provided in the conductive member.

4. Further comprising a strip line for feeding the antenna element, 4. The inspection device according to claim 1, wherein the strip line is located on a surface of the insulating member opposite to a surface facing the ground surface.

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