JP2020159923A - Circuit board, probe card, and inspection instrument - Google Patents

Abstract

To provide a circuit board that is used for a probe card for inspection of an image pick-up device, and is excellent in strength.SOLUTION: A circuit board 100 comprises: an insulating substrate 10 that has a first surface 11 and a second surface 12 on an opposite side of the first surface 11, and through holes 13 that penetrate from the first surface 11 to the second surface 12, wherein first openings 13a in the first surface 11 are larger than second openings 13b in the second surface 12; and a circuit conductor 20 that includes connection pads 21 being arranged on a periphery of the first openings 13a on the first surface 11.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to circuit boards for probe cards, probe cards, and inspection devices.

As a probe card for electrically inspecting a light receiving element such as an image sensor on a wafer, a probe card having a probe pin installed on a circuit board having a through hole is used. Project the inspection light or pattern onto the solid-state image sensor through the through hole of the circuit board, and check whether the signal output by the image sensor corresponds to the inspection light or pattern. The quality of the image sensor is determined by (see, for example, Patent Document 1). Some devices that project light for inspection are equipped with a plurality of lenses for making the light from the light source parallel light and a diaphragm device for adjusting the intensity of the light (for example, a patent). See Reference 2).

Japanese Unexamined Patent Publication No. 2014-232794 JP-A-2007-208253

However, in order to prevent the shadow of the circuit board from being cast on the image pickup region (light receiving region) of the image pickup element (light receiving element) regardless of whether the inspection light is parallel light or light that spreads from the light source. , The size of the through hole must be equal to or larger than the size of the imaging area. Since the rigidity of a circuit board having a large number of through holes corresponding to a large number of image pickup elements on a wafer is lowered, the possibility that the circuit board itself is destroyed is likely to increase. Even if it does not break, if the surface facing the wafer is distorted due to the decrease in rigidity, the height will vary even if the probe pins are connected, and the reliability of the electrical connection with the electrodes of the elements on the wafer will increase. There was a possibility that it would drop. A ceramic substrate with high rigidity is used for the circuit board, but if low thermal expansion ceramics such as mullite are used to reduce the difference in thermal expansion from the wafer, the strength is smaller than that of alumina etc., so the rigidity is reduced due to the through holes. Could be more problematic.

The circuit board according to one aspect of the present disclosure has a first surface and a second surface opposite to the first surface, penetrates from the first surface to the second surface, and has a first surface on the first surface. It includes an insulating substrate in which one opening has a through hole larger than the second opening on the second surface, and a circuit conductor including connection pads arranged around the first opening on the first surface.

The probe card of one aspect of the present disclosure includes a circuit board having the above configuration and a probe pin electrically connected to the connection pad.

The inspection device of one aspect of the present disclosure includes a probe card having the above configuration and a light source unit arranged at a position corresponding to the through hole of the circuit board.

According to the circuit board of one aspect of the present disclosure, since the entire area of the through hole is not larger than the image pickup region of the image pickup device to be inspected, the decrease in rigidity due to the through hole is suppressed, and distortion and destruction are unlikely to occur. It becomes a circuit board.

According to the probe card of one aspect of the present disclosure, since the circuit board having the above configuration is included, it is possible to provide a probe card having high rigidity and capable of reliable inspection.

According to the inspection device of one aspect of the present disclosure, since the probe card having the above configuration and the light source unit arranged at a position corresponding to the through hole of the circuit board are provided, a light receiving element such as an image sensor is provided. It will be possible to carry out the inspection of.

(A) is a plan view showing an example of a circuit board, and (b) is a cross-sectional view taken along the line BB of (a). It is sectional drawing which shows an example of the probe card using the circuit board shown in FIG. 1 and an example of the main part of an inspection apparatus. It is sectional drawing which shows the main part of the circuit board shown in FIG. 1 in an enlarged manner. It is sectional drawing which shows the main part of another example of a circuit board enlarged. It is sectional drawing which shows the main part of another example of a circuit board enlarged. It is sectional drawing which shows the main part of another example of a circuit board enlarged. It is sectional drawing which shows the main part of another example of a circuit board enlarged. It is sectional drawing which shows the main part of another example of a circuit board enlarged. It is sectional drawing which shows the main part of another example of a circuit board enlarged. It is sectional drawing which shows the main part of another example of a circuit board enlarged. It is sectional drawing which shows the main part of another example of a circuit board enlarged.

The circuit board, probe card, and inspection device of the embodiments of the present disclosure will be described with reference to the drawings. The figures used in the following description are schematic, and the distinction between the top and bottom is for convenience of explanation and does not regulate the top and bottom when the circuit board or the like is actually used. 1 (a) is a plan view showing an example of a circuit board, and FIG. 1 (b) is a cross-sectional view taken along the line BB of FIG. 1 (a). FIG. 2 is a cross-sectional view showing an example of a probe card using the circuit board shown in FIG. 1 and an example of a main part of an inspection device. FIG. 3 is an enlarged cross-sectional view showing a main part of the circuit board shown in FIG. 4 to 11 are enlarged cross-sectional views showing a main part of another example of the circuit board. Note that FIGS. 3 to 11 show a state in which the light receiving element on the wafer is inspected by an inspection device using a probe card including a circuit board.

The circuit board 100 of the present disclosure includes an insulating substrate 10 and a circuit conductor 20 including a connection pad 21. The insulating substrate 10 has a first surface 11 and a second surface 12 on the opposite side of the first surface 11, and has a through hole 13 penetrating from the first surface 11 to the second surface 12. Connection pads 21 are arranged around the first opening 13a on the first surface 11 of the through hole 13. The first opening 13a on the first surface 11 of the through hole 13 is larger than the second opening 13b on the second surface 12.

The vertical cross-sectional shape of the through hole 13 is various as shown in FIGS. 1 to 11, but in any form, the first opening 13a of the through hole 13 is larger than the second opening 13b. The shape of the opening is not particularly limited, but in the examples shown in FIGS. 1 to 11, the shapes of the first opening 13a and the second opening 13b are circular. Therefore, in the examples shown in FIGS. 3 to 11, the size or diameter of the first opening 13a is shown as D1, and the diameter of the second opening 13b is shown as D2. The first opening 13a facing the light receiving area 821 is the light receiving area so that the light L for inspection emitted from the light source unit 500 of the inspection device 700 irradiates the entire area of the light receiving area 821 of the light receiving element 820 to be inspected. It is equal to or larger than the size of 821. The light receiving region 821 occupies a large part of the area of the light emitting element, and the area occupied by the light receiving region 821 is large in the wafer 800 in which a large number of light emitting elements are arranged. Therefore, in the circuit board 100 arranged to face the wafer 800, the proportion of the through hole 13 at the position facing (overlapping) the light receiving region 821 also increases. In the circuit board 100 of the present disclosure, the first opening 13a of the through hole 13 is larger than the second opening 13b, and conversely, the second opening 13b is smaller than the first opening 13a. Since the entire area of the through hole 13 is not equal to or larger than the light receiving region 821, the ratio of the through hole 13 to the circuit board 100 becomes small. Therefore, the decrease in rigidity of the insulating substrate 10 due to the through hole 13 is suppressed, and the circuit board 100 is less likely to be distorted or broken. Further, as the light L for inspection, light that spreads from the second opening 13b toward the first opening 13a can be used. Therefore, when such a circuit board 100 is used, a device for making parallel light is provided. It can be a low-cost inspection device 700.

With respect to the size D1 of the first opening 13a as described above, the size D2 of the second opening 13b can be made, for example, a size that is not damaged by the light source portion 500 of the inspection device 700. If the light source unit 500 can be arranged close to each other, the light source unit 500 does not need to have a high output, so that the inspection device 700 can be made at a lower cost.

The form in which the size D1 of the first opening 13a of the through hole 13 is larger than the size D2 of the second opening 13b is various as in the examples shown in FIGS. 3 to 11. The through hole 13 in the circuit board 100 of the example shown in FIG. 11 is continuously enlarged from the second opening 13b to the first opening 13a. In such a case, since the inner surface of the through hole 13 does not have a bent portion and there is no portion where stress is likely to be concentrated, the possibility of cracks or the like is reduced.

The through hole 13 in the circuit board 100 of the example shown in FIGS. 3 to 10 has an increased size in the middle of the thickness direction of the insulating substrate 10 from the second opening 13b to the first opening 13a. The through hole 13 in the circuit board 100 of the example shown in FIG. 9 has a larger size on the second surface 12 side than the center in the thickness direction of the insulating substrate 10. Further, the through holes 13 in the circuit board 100 of the example shown in FIG. 10 are large in two places, a portion on the first surface 11 side from the center and a portion on the second surface 12 side from the center in the thickness direction of the insulating substrate 10. Is getting bigger. On the other hand, the through hole 13 in the circuit board 100 of the example shown in FIGS. 3 to 8 has a larger size on the first surface 11 side than the center in the thickness direction of the insulating substrate 10.

In this way, the circuit board 100 has a through hole 13 larger than the second opening 13b on the first surface 11 side of the center in the thickness direction of the insulating substrate 10. In the case of such a through hole 13, the size of the through hole 13 is smaller (D2) than in the example shown in FIG. 11, in which the through hole 13 is continuously enlarged from the second opening 13b to the first opening 13a. The ratio of the portion) becomes large, and the through hole 13 as a whole becomes smaller. Therefore, the decrease in rigidity of the insulating substrate 10 due to the through hole 13 is further suppressed, and the circuit board 100 is less likely to be distorted or broken.

The through holes 13 in the circuit board 100 of the examples shown in FIGS. 3 to 8 are larger in size on the first surface 11 side than the center in the thickness direction of the insulating substrate 10, but the forms are different from each other. The size of the through hole 13 in the circuit board 100 of the example shown in FIGS. 7 and 8 is continuously and gradually increased from D2 to D1, and the inner surface of the through hole 13 in this portion is the first surface 11. And it is inclined with respect to the second surface 12 (with respect to the thickness direction of the insulating substrate 10). Therefore, the size of the through hole 13 becomes small, and the shape becomes such that stress is hard to concentrate. Therefore, in terms of strength, the through hole 13 having such an inclined inner surface can be obtained. The through hole 13 in the circuit board 100 of the example shown in FIGS. 3 to 6 has an inner surface of the through hole 13 perpendicular to the first surface 11 and the second surface 12, regardless of the size of the diameter. Such a through hole 13 can be easily formed with higher positional accuracy with respect to the light L from the light source unit 500 as compared with the one having an inclined surface.

The insulating substrate 10 in the circuit board 100 of the example shown in FIGS. 1 to 3 is made of the same material, for example, ceramics in the thickness direction. On the other hand, the insulating substrate 10 in the circuit board 100 of the examples shown in FIGS. 4 to 11 is made of different materials on the first surface 11 side and the second surface 12 side. The insulating substrate 10 is composed of a resin substrate portion 10a on the first surface 11 side and a ceramic substrate portion 10b on the second surface 12 side. The outer surface (upper surface) of the resin substrate portion 10a is the first surface 11, and the outer surface (lower surface) of the ceramic substrate portion 10b is the second surface 12. The resin substrate portion 10a is laminated on the upper surface of the ceramic substrate portion 10b. Since the through hole 13 penetrates from the first surface 11 to the second surface 12, the resin substrate portion 10a has the first opening 13a, and the ceramic substrate portion 10b has the second opening 13b. In this way, the insulating substrate 10 can be a circuit board 100 having a laminated structure of a resin substrate portion 10a having a first opening 13a and a ceramic substrate portion 10b having a second opening 13b.

The connection pads 21 arranged around the first opening 13a are portions to which the probe pins 200 are connected when the circuit board 100 is used as the probe card 300. Therefore, since the connection pad 21 corresponds to the size and arrangement of the electrodes 822 in the light receiving element 820 on the wafer 800 to be inspected, the size is small and the connection pads 21 are often arranged at high density. When the portion including the first surface 11 of the insulating substrate 10 facing the wafer 800 and where the connection pad 21 is arranged is composed of the resin substrate portion 10a, wiring or the like can be formed by using a thin film or the like, so that it is fine. The circuit board 100 includes a circuit conductor 20 including connection pads 21 arranged at high density. On the other hand, if the portion including the second surface 12 that does not require a high-density circuit conductor 20 as compared with the first surface 11 is composed of the ceramic substrate portion 10b, the rigidity is high even if a large number of through holes 13 are provided. It becomes the circuit board 100. As described above, assuming that the insulating substrate 10 is a circuit board 100 having a laminated structure of a resin substrate portion 10a having a first opening 13a and a ceramic substrate portion 10b having a second opening 13b, a high-density circuit conductor is used. The circuit board 100 has a high rigidity and includes 20 and a plurality of through holes 13.

As described above, in the circuit board 100 of the example shown in FIG. 4, the through hole 13 is larger than the second opening 13b on the first surface 11 side of the center in the thickness direction of the insulating substrate 10. The size of the through hole 13 is constant at D1 in the thickness direction of the resin substrate portion 10a. The size of the opening on the upper surface of the ceramic substrate portion 10b is D1 which is the same as the size of the resin substrate portion 10a, and the size of the through hole 13 between the upper surface and the lower surface is D2. On the other hand, in the circuit board 100 of the example shown in FIG. 5, the size D1 of the first opening 13a of the through hole 13 is larger than the example shown in FIG. 4, and the size D1 of the through hole 13 in the resin substrate portion 10a. Is larger than the size of the opening D1c on the upper surface of the ceramic substrate portion 10b. Since the size of the opening in the resin substrate portion 10a is the same D1 on the upper surface and the lower surface, the size D1 of the opening on the lower surface of the resin substrate portion 10a is larger than the size D1c of the opening on the upper surface of the ceramic substrate portion 10b. You can also do it. As described above, at the laminated interface between the resin substrate portion 10a and the ceramic substrate portion 10b, the opening of the resin substrate portion 10a can be a circuit board 100 larger than the opening of the ceramic substrate portion 10b. With such a configuration, the inner surface of the through hole 13 in the resin substrate portion 10a is separated from the light L from the light source portion 500, and the resin substrate portion 10a is hidden behind the ceramic substrate portion 10b when viewed from the light source portion 500. It becomes. Depending on the type of the resin of the resin substrate portion 10a and the light L from the light source portion 500, the resin of the resin substrate portion 10a may be deteriorated by the light L. Since the resin is separated from the light L, the possibility of such deterioration is reduced, and the reliability is lowered due to defects such as a change in electrical characteristics due to deterioration of the resin and peeling from the ceramic substrate portion 10b. The circuit board 100 has a reduced possibility. Further, when the resin substrate portion 10a and the ceramic substrate portion 10b are separately manufactured and laminated, the inner surface of the through hole 13 in the resin substrate portion 10a becomes the through hole 13 in the ceramic substrate portion 10b due to the positional deviation during lamination. The possibility of being located inside the inner surface of the is reduced. In the circuit board 100 of the example shown in FIG. 6, the size of the opening on the lower surface of the resin substrate portion 10a is the same as the size D1 of the first opening 13a, and the size D1c of the opening on the upper surface of the ceramic substrate portion 10b is the second. It is the same as the size D2 of the opening 13b. Therefore, also in this example, at the lamination interface between the resin substrate portion 10a and the ceramic substrate portion 10b, the opening of the resin substrate portion 10a is larger than the opening of the ceramic substrate portion 10b, and the same effect as the example shown in FIG. 5 is obtained.

The probe card 300 can be manufactured by connecting the probe pin 200 to such a circuit board 100. That is, the probe card 300 of the present disclosure includes a circuit board 100 having the above configuration and a probe pin 200 electrically connected to the connection pad 21. Since the circuit board 100 having the above configuration is included, the probe card 300 has high rigidity and can be reliably inspected.

Further, the inspection device 700 of the present disclosure includes the probe card 300 and a light source unit 500 arranged at a position corresponding to the through hole 13 of the circuit board 100. Since the probe card 300 including the circuit board 100 having the above configuration is provided, it is possible to reliably inspect the light receiving element 820 such as the image pickup element.

The circuit board 100 includes an insulating substrate 10 having a through hole 13 and a circuit conductor 20. The insulating substrate 10 is a basic part of the circuit board 100, and functions as an electrical insulator for arranging circuit conductors 20 such as a plurality of connection pads 21 so as to be electrically insulated from each other. The insulating substrate 10 is made of ceramics in the examples shown in FIGS. 1 to 3. In the examples shown in FIGS. 4 to 11, the insulating substrate 10 is configured by laminating a resin substrate portion 10a and a ceramic substrate portion 10b. It can also be said that the insulating substrate 10 of the example shown in FIGS. 1 to 3 is composed of only the ceramic substrate portion 10b.

The insulating substrate 10 is an octagonal plate-shaped flat plate in the example shown in FIG. 1, but may be another polygon such as a quadrangle or a circle. The dimensions of the ceramic substrate portion 10b in a plan view are appropriately set according to, for example, the dimensions in a plan view of the wafer 800 to be inspected when used as a probe card 300, an inspection method, and the like. It may have the same size as the wafer 800, or may have a different size. For example, it is used for a probe card 300 having a probe pin 200 corresponding to a light receiving element 820 arranged in an area of about a quarter of the area of the wafer 800 and inspecting one wafer 800 in four times. If it is the circuit board 100, the size of the circuit board 100 (insulating substrate 10) may be smaller than that of the wafer 800. If the circuit board 100 is used for the probe card 300 provided with the probe pins 200 corresponding to the light receiving elements 820 arranged over the entire area of the wafer 800, the circuit board 100 is used in order to increase the size and spacing of the external terminals 22 described later. The size of the substrate 100 (insulating substrate 10) can be made larger than that of the wafer 800.

The insulating substrate 10 has a through hole 13 penetrating from the first surface 11 to the second surface 12. The size, shape, and arrangement of the through hole 13 can be set according to the size, shape, and arrangement of the light receiving element 820 on the wafer 800 to be inspected. The size of the first opening 13a of the through hole 13 is the same as or larger than the size of the light receiving region 821 as described above. The vertical cross-sectional shape of the through hole 13 can be, for example, the shape shown in FIGS. 3 to 11 described above. The shape of the through hole 13 in a plan view is circular in the example shown in FIG. 1, but it may be another shape such as a quadrangular shape. In the case of a polygon such as a quadrangle, it can be a quadrangle with rounded corners. As a result, cracks or the like starting from the corners of the through holes 13 are less likely to occur, and the strength reduction of the insulating substrate 10 due to the through holes 13 can be suppressed. The same effect can be obtained when the through hole 13 is circular. The arrangement of the through holes 13 does not have to be arranged so as to correspond one-to-one with the light receiving element 820 on the wafer 800. For example, in the examples shown in FIGS. 3 to 11, three light receiving elements 820 are arranged on the wafer 800, whereas the circuit board 100 facing the three light receiving elements 820 is provided with two through holes 13. .. Every other through hole 13 is arranged with respect to the arrangement of the light receiving element 820, and the arrangement pitch of the through holes 13 is twice the arrangement pitch of the light receiving element 820. This is because if the through holes 13 are provided one-to-one with respect to the light receiving element 820, the distance between the adjacent through holes 13 becomes small, and the rigidity and strength of the insulating substrate 10 decrease. When the distance between the light receiving elements 820 on the wafer 800 is large and the strength of the insulating substrate 10 can be secured, the through holes 13 can be provided at positions corresponding to the arrangement of the light receiving elements 820 on a one-to-one basis. In the circuit board 100 of the example shown in FIG. 1, the arrangement pitch of the through holes 13 in the horizontal direction is twice the arrangement pitch of the light receiving element 820 on the wafer 800, and the arrangement pitch of the through holes 13 in the vertical direction receives light. An example showing the same arrangement pitch as the element 820 is shown. The inspection of the light receiving element 820 on the wafer 800 can be performed twice.

The connection pads 21 are arranged around the first opening 13a of the through hole 13 on the first surface 11 of the insulating substrate 10. An external terminal 22 is provided on the second surface 12 of the insulating substrate 10, and the connection pad 21 and the external terminal 22 are electrically connected by an internal conductor 23 provided inside the insulating substrate 10. .. The connection pad 21 is a portion to which the probe pin 200 is connected when the circuit board 100 is used as the probe card 300. The connection pads 21 have a number and arrangement corresponding to the electrodes 822 of the light receiving element 820 to be inspected, and are provided around the through holes 13 at positions corresponding to the light receiving region 821 of the light receiving element 820. In the example shown in FIG. 1, two rows of connection pads 21 are arranged so as to sandwich one through hole 13, but they are arranged so as to surround the through hole 13 according to the arrangement of the electrodes 822 of the light receiving element 820. You may. The external terminal 22 is an electrode for connecting the probe card 300 to the circuit of the inspection device 700. The inner conductor 23 has a through conductor penetrating the insulating substrate 10 in the thickness direction and a wiring layer extending in the surface direction. The wiring layer of the inner conductor 23 includes a linear line conductor for transmitting a signal and a large-area so-called solid conductor such as a ground conductor and a power supply conductor. In the inspection using the probe card 300, the inspection is performed from the light receiving element 820 on the wafer 800 through the probe pin 200 in contact with the electrode 822 of the light receiving element 820, the connection pad 21 of the circuit board 100, the internal conductor 23, and the external terminal 22. The signal is transmitted to the circuit of the device 700. The size and spacing of the connection pads 21 on the first surface 11 are fine because they correspond to the electrodes 822 of the light receiving element 820. Deployed by the internal conductor 23 within the insulating substrate 10, the size and spacing of the external terminals 22 on the second surface 12 are larger than those of the connection pad 21. Therefore, the probe card 300 (circuit board 100) makes it easy to electrically connect the fine electrodes 822 of the light receiving element 820 to the circuit of the inspection device 700.

The ceramic substrate portion 10b, which is the insulating substrate 10 or is a portion of the insulating substrate 10 on the second surface 12 side, includes, for example, a plurality of ceramic insulating layers laminated with each other. The ceramic substrate portion 10b has a function of ensuring the overall rigidity of the circuit board 100, for example. The ceramic substrate portion 10b enhances the rigidity of the circuit board 100, and suppresses deformation when it is used as a probe card 300, for example, and pressed against a wafer 800 for inspection.

The ceramic substrate portion 10b (ceramic insulating layer) is made of, for example, a ceramic sintered body such as an aluminum oxide sintered body, an aluminum nitrided sintered body, a silicon carbide sintered body, a mulite sintered body, or a glass ceramic. Some of the mullite sintered bodies and glass ceramics have a smaller coefficient of thermal expansion than the other ceramic sintered bodies described above, and a thermal expansion system close to the coefficient of thermal expansion of silicon of the substrate 810 of the wafer 800 to be inspected. Have. Therefore, when the probe card 300 is used for inspection, the position of the electrode 822 on the wafer 800 and the probe pin 200 are unlikely to shift due to the temperature of the environment at the time of inspection. Therefore, it is possible to provide the probe card 300 and the inspection device 700 having excellent inspection accuracy. On the other hand, some of the mullite sintered bodies and glass ceramics have lower strength than the other ceramic sintered bodies described above. Therefore, it is more effective to configure the through hole 13 provided in the insulating substrate 10 as described above.

The thickness of the ceramic substrate portion 10b, the number of layers of the ceramic insulating layer, the number of electrodes 822 of the light receiving element 820 to be inspected, the number and arrangement of circuit conductors 20 according to the electrical characteristics, and other electrical conditions, the ceramic substrate portion 10b It is appropriately set according to various conditions such as rigidity and economic efficiency required for the above.

The ceramic substrate portion 10b can be manufactured as follows, for example, when it is made of an aluminum oxide sintered body. First, a raw material powder containing aluminum oxide powder and a powder such as silicon oxide as a sintering aid component as a main component is kneaded with an organic solvent and a binder to form a slurry, and this slurry is used by a doctor blade method, a lip coater method, etc. A ceramic green sheet (hereinafter, also referred to as a green sheet) to be a ceramic insulating layer is produced by molding into a sheet by the molding method of. Next, a plurality of green sheets are laminated to prepare a laminated body. After that, the ceramic substrate portion 10b can be manufactured by firing this laminate at a temperature of about 1300 to 1600 ° C.

The inner conductor 23 and the outer terminal 22 of the circuit conductor 20 in the ceramic substrate portion 10b include, for example, a metal material such as tungsten, molybdenum, manganese or copper, or an alloy material of these metal materials as a conductor component. For example, these metal materials (alloy materials) are sintered at the same time as the ceramic green sheet is fired to form metallized conductors on the surface and inside of the ceramic substrate portion 10b. For example, it may contain a solid component such as glass or ceramics in order to enhance the sinterability or the bonding strength with ceramics.

When the wiring layer and the outer terminal 22 of the inner conductor 23 of the circuit conductor 20 are, for example, a tungsten metallized layer, a metal paste prepared by mixing tungsten powder with an organic solvent and an organic binder is used as a ceramic insulating layer. It can be formed by printing at a predetermined position on the green sheet by a method such as a screen printing method and firing together with the green sheet. Further, the through conductor of the inner conductor 23 is formed by providing a through hole at a predetermined position on the green sheet prior to printing the metal paste and filling the through hole with the same metal paste as described above. be able to.

The connection pad 21 in the case where the insulating substrate 10 is composed of only the ceramic substrate portion 10b can be formed of the metallized conductor as described above, but can also be formed of a thin film conductor. By forming with a thin film conductor, it is possible to easily form a fine connection pad 21 as compared with the metallized conductor. In this case, the first surface 11 of the insulating substrate 10 made of ceramics can be formed with high accuracy by flattening it by polishing.

The connection pad 21 on the ceramic substrate portion 10b can be manufactured, for example, as follows. For example, using a thin film forming method such as a sputtering method, first, a bonded metal layer of about 0.1 to 3 μm of titanium, chromium, or the like is formed on the entire upper surface of the ceramic substrate portion 10b having the outer terminal 22 and the inner conductor 23 of the metallized conductor. To form. Next, a main conductor layer such as copper having a size of about 2 to 10 μm is formed on the entire surface of the bonded metal layer to form a conductive thin film layer. A barrier layer or the like may be formed if necessary. Then, the thin film connection pad 21 can be formed by patterning the conductive thin film layer by photolithography. A nickel film of about 1 to 10 μm and a gold film of about 0.1 to 3 μm are sequentially formed on the surface of the connection pad 21 to protect the surface of the connection pad 21 and to improve the bondability of brazing material, solder, etc. Can be enhanced. The nickel film and the gold film can be formed of a plating film or a thin film obtained by electrolytic plating.

When the insulating substrate 10 is configured by laminating the resin substrate portion 10a and the ceramic substrate portion 10b as in the examples shown in FIGS. 4 to 11, the ceramic substrate portion 10b as described above and the ceramic substrate portion 10b will be described below. It can be manufactured by laminating the resin substrate portion 10a.

The resin substrate portion 10a is a portion for providing a fine and high-density circuit conductor 20 including a fine connection pad 21 corresponding to the electrode 822 of the light receiving element 820 on the ceramic substrate portion 10b. Since the circuit conductor 20 of the ceramic substrate portion 10b is connected to an external measuring device or the like, the pattern is not fine. In order to connect the connection pad 21 and the circuit conductor 20 of the ceramic substrate portion 10b, the resin substrate portion 10a is provided with an internal conductor 23 made of a thin film conductor. Since the surface roughness of the uppermost resin layer on which the connection pad 21 is formed in the resin substrate portion 10a is smaller than the surface roughness of the ceramic substrate portion 10b, the connection pad is formed in a fine pattern by the thin film forming technique. It is easy to form 21.

The resin substrate portion 10a has the same shape as the ceramic substrate portion 10b in a plan view, and the ceramic substrate portion 10b and the resin substrate portion 10a provided on the ceramic substrate portion 10b form an integral flat circuit board 100.

The resin substrate portion 10a includes a plurality of laminated resin layers. The number and thickness of the resin layer are set by the number of electrodes 822 of the light receiving element 820 to be inspected, and are set so that they can be developed so as to be connected to the circuit conductor 20 of the ceramic substrate portion 10b.

The resin layer of the resin substrate portion 10a includes, for example, a polyimide resin, a polyamideimide resin, a siloxane-modified polyamideimide resin, a siloxane-modified polyimide resin, a polyphenylene sulfide resin, a total aromatic polyester resin, a BCB (benzocyclobutene) resin, and an epoxy resin. It is composed of an insulating resin such as bismaleimide triazine resin, polyimideene ether resin, polyquinoline resin, and fluororesin.

The resin layer may contain a filler for adjusting the moldability and the coefficient of thermal expansion. Examples of the filler include barium sulfate, barium titanate, amorphous silica, crystalline silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, silicon nitride, and aluminum nitride. Examples thereof include inorganic fillers such as boron nitride, alumina, magnesium oxide, magnesium hydroxide, titanium oxide, mica, Neuburg silica soil, organic bentonite, and zirconium phosphate. One of these may be used alone, or two or more thereof may be used in combination as appropriate.

The resin substrate portion 10a is formed, for example, by laminating and adhering a plurality of film-shaped resin layers, by applying a liquid precursor resin and curing it to form a resin layer, and then forming a liquid resin layer on the resin substrate portion 10a. It can be produced by a method of repeating the step of forming a resin layer with a precursor liquid resin. The method of laminating a film-like resin layer is more efficient.

The circuit conductor 20 of the resin substrate portion 10a includes a connection pad 21 provided on the upper surface of the resin substrate portion 10a, which is the first surface 11 of the insulating substrate 10, and an internal conductor 23 provided inside the resin substrate portion 10a. are doing. The inner conductor 23 is provided between layers of a plurality of resin layers, and has a thin film wiring layer that mainly forms a circuit in a plane and a thin film through conductor that electrically connects the upper and lower thin film wiring layers. ing. The thin film penetrating conductor that penetrates the lowermost resin layer of the resin substrate portion 10a and exposes the end surface to the lower surface of the resin substrate portion 10a is electrically connected to the wiring layer on the upper surface of the ceramic substrate portion 10b. As a result, the circuit conductor 20 (connection pad 21 and internal conductor 23) provided on the resin substrate portion 10a and the circuit conductor 20 (internal conductor 23 and external terminal 22) provided on the ceramic substrate portion 10b are electrically connected. Will be done.

The connection pad 21 and the internal conductor 23 of the resin substrate portion 10a may be formed, for example, as follows. First, a resist film having openings corresponding to the thin film penetrating conductor and the thin film wiring layer is formed on the resin layer, and a recess corresponding to the thin film wiring layer and a penetration corresponding to the thin film penetrating conductor are formed by etching or laser processing. Form a hole. The recess corresponding to the thin film wiring layer is not always necessary, but by providing the recess, the joining reliability between the thin film wiring and the resin layer can be improved. Next, by a thin film forming method such as a thin film deposition method, a sputtering method, or an ion plating method, for example, a chromium (Cr) -copper (Cu) alloy layer or titanium (Ti) -copper ( Cu) A base conductor layer composed of an alloy layer is formed. Next, the thin film through conductor and the thin film wiring layer can be formed by filling the recesses and through holes with a metal having a small electric resistance such as copper or gold by plating or the like and peeling off the resist.

The method of forming a laminated structure of the resin substrate portion 10a and the ceramic substrate portion 10b is, for example, a method of producing the resin substrate portion 10a and adhering it to the upper surface of the ceramic substrate portion 10b, or a method of adhering the resin to the upper surface of the ceramic substrate portion 10b. There is a method of stacking layers one by one. The method of laminating the resin layers one by one may be either a method using the film-like resin described above or a method using a liquid precursor resin. It is more efficient to prepare the resin substrate portion 10a and bond the plurality of resin layers (and the circuit conductor 20) to the upper surface of the ceramic substrate portion 10b at once.

By attaching the probe pin 200 to the connection pad 21 of the circuit board 100 produced in this manner, the probe card 300 is formed. The probe pin 200 is mechanically and electrically connected to the connection pad 21.

The probe pin 200 is made of, for example, a metal such as nickel or tungsten. If the probe pin 200 is made of nickel, it is produced, for example, as follows. First, female molds of a plurality of probe pins are formed on one surface of a silicon substrate by etching. The female mold is arranged so as to correspond to the arrangement of the connection pad 21 of the circuit board 100. Next, a metal made of nickel is adhered to the surface of the silicon substrate on which the female mold is formed by a plating method, and the female mold is further embedded with nickel. Nickel adhered to the upper surface of the silicon substrate other than the nickel embedded in the female mold is removed by processing such as an etching method to prepare a silicon substrate in which nickel probe pins are embedded. The nickel probe pin embedded in the silicon substrate is joined to the connection pad 21 of the circuit board 100 with a conductive bonding material such as solder. Then, by removing the silicon substrate with an aqueous potassium hydroxide solution, a probe card 300 in which the probe pin 200 is bonded to the connection pad 21 of the circuit board 100 can be obtained.

The inspection device 700 includes a probe card 300 as described above, and a light source unit 500 arranged at a position corresponding to a through hole 13 of the circuit board 100. In the inspection device of the example shown in FIG. 2, the inspection device 700 includes a control unit (not shown) that controls inspection and the like, and a connection board 400 that electrically connects the probe card 300 and the circuit of the control unit. It has. The connection terminal 402 that is electrically connected to the wiring 401 of the connection board 400 and the external terminal 22 of the probe card 300 (the circuit board 100) are electrically connected. The connection terminal 402 in this example is made of metal having a spring property, and by bringing the connection board 400 close to the probe card 300, the connection terminal 402 is pressed against the external terminal 22 to make an electrical connection.

In the example shown in FIG. 2, the light source unit 500 for irradiating the inspection light is provided on the same surface as the connection terminal 402 of the connection board 400. The light source unit 500 in this example includes a light emitting element or the like, and is provided at a position corresponding to each of the second openings 13b of the through hole 13 of the circuit board 100. A portion that actually emits light may be arranged elsewhere, and only a portion that emits an optical signal transmitted by an optical fiber or the like may be arranged as a light source unit 500 at a position corresponding to the through hole 13.

In the inspection device 700, the light source unit 500 is also connected to the control unit, and at the time of inspection, the light for inspection is transmitted from the light source unit 500 to the wafer 800 through the through hole 13 of the probe card 300 (circuit board 100) under the control of the control unit. The upper light receiving element 820 (light receiving region 821) is irradiated. The light for inspection is irradiated, and the light is converted into an electric signal in the light receiving region 821 of the light receiving element 820. This electric signal is transmitted to the control unit and the processing unit (not shown) through the electrode 822 of the light receiving element 820, the probe pin 200, the circuit conductor 20 of the circuit board 100, the connection terminal 402 of the connection board 400, and the wiring 401, and the inspection result. Is processed as.

What is inspected by such an inspection device 700 is a plurality of light receiving elements 820 formed on the wafer 800. The light receiving element 820 converts the light received in the light receiving region 821 into an electric signal and outputs the light, and is, for example, an image pickup device such as a CCD (Charge Coupled Device) or a CMOS (Complementary metal-oxide-semiconductor).

The circuit board 100, the probe card 300, and the inspection device 700 of the present disclosure are not limited to the above-mentioned specific examples, and can be appropriately changed without departing from the gist of the invention.

10 ... Insulation substrate 10a ... Resin substrate portion 10b ... Ceramic substrate portion 11 ... First surface 12 ... Second surface 13 ... Through hole 13a ... First Opening 13b ... Second opening 20 ... Circuit conductor 21 ... Connection pad 22 ... External terminal 23 ... Internal conductor 100 ... Circuit board 200 ... Probe pin 300 ...・ ・ Probe card 400 ・ ・ ・ Connection board 401 ・ ・ ・ ・ Wiring 402 ・ ・ ・ ・ Connection terminal 500 ・ ・ ・ ・ Light source 700 ・ ・ ・ Inspection device 800 ・ ・ ・ Wafer 810 ・ ・ ・ Base 820 ・ ・ ・Light receiving element 821 ... Light receiving area 822 ... Electrode

Claims (6)

It has a first surface and a second surface opposite to the first surface, penetrates from the first surface to the second surface, and the first opening in the first surface is the second opening in the second surface. Insulated substrates with larger through holes and
A circuit conductor including connection pads arranged around the first opening on the first surface, and
A circuit board that features. The circuit board according to claim 1, wherein the through hole is larger than the second opening on the first surface side of the center in the thickness direction of the insulating substrate. The circuit board according to claim 1 or 2, wherein the insulating substrate has a laminated structure of a resin substrate portion having the first opening and a ceramic substrate portion having the second opening. The circuit board according to claim 3, wherein the opening of the resin substrate portion is larger than the opening of the ceramic substrate portion at the laminated interface between the resin substrate portion and the ceramic substrate portion. The circuit board according to any one of claims 1 to 4.
A probe card comprising a probe pin that is electrically connected to the connection pad. An inspection device including the probe card according to claim 5 and a light source unit arranged at a position corresponding to the through hole of the circuit board.

Images