JP7441478B2 - connection device - Google Patents

Description

The present invention relates to a connection device used for testing the characteristics of an object to be tested.

Using silicon photonics technology, a semiconductor element (hereinafter referred to as an "optical device") having an electric circuit for propagating electrical signals and an optical circuit for propagating optical signals is formed on a silicon substrate or the like. In order to test the characteristics of an optical device in a wafer state, an optical fiber or the like is used as an optical connector to connect the optical device and a testing device.

For example, a method has been disclosed in which the characteristics of an optical device to be inspected are acquired by bringing the tip of an optical fiber held in a probe body close to each other (see Patent Document 1).

US Patent Application Publication No. 2006/0008226A1

In the inspection of optical devices, the optical device and inspection equipment are connected using a connecting device that connects an electrical connector that propagates an electrical signal to the optical device, and connects an optical connector that propagates an optical signal to the optical device. This is effective. However, development of such a connecting device has not progressed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a connection device that can connect both an electrical connector that propagates an electric signal and an optical connector that propagates an optical signal to an optical device, and a method for manufacturing the same.

According to one aspect of the present invention, there is provided a connection device used for testing a semiconductor device having an electrical signal terminal through which an electric signal propagates and an optical signal terminal through which an optical signal propagates, the connection device including a plurality of optical signal terminals and an optical a plurality of optical connectors made of optical fibers or optical waveguides that are connected to each other, a plurality of electrical connectors that are paired with the optical connectors and electrically connected to an electrical signal terminal, and an optical signal terminal of the optical connector. A block for fixing the optical connector is attached with the optical connection end exposed to the main surface, and the block is movable along the thickness direction perpendicular to the main surface. A circuit board on which electrical connectors are installed and an electrical circuit electrically connected to the electrical connectors is formed, and the position of the block in the thickness direction with respect to the circuit board is adjusted, and the circuit board is A connection device is provided that includes a position adjustment mechanism that adjusts the relative position of the block with respect to the substrate.

According to the present invention, it is possible to provide a connecting device that can connect both an electrical connector that propagates an electric signal and an optical connector that propagates an optical signal to an optical device, and a method for manufacturing the same.

FIG. 1 is a schematic diagram showing the configuration of a connection device according to an embodiment of the present invention. It is a typical perspective view showing an example of a position adjustment mechanism of a connecting device concerning an embodiment of the present invention. FIG. 1 is a schematic diagram (part 1) for explaining a method for manufacturing a connecting device according to an embodiment of the present invention. FIG. 2 is a schematic diagram (part 2) for explaining the method for manufacturing the connection device according to the embodiment of the present invention. FIG. 2 is a schematic plan view showing an example of the arrangement of optical connectors and electrical connectors of the connection device according to the embodiment of the present invention. FIG. 2 is a schematic perspective view showing an example of the structure of a stiffener of a connecting device according to an embodiment of the present invention. FIG. 1 is a perspective view showing the configuration of a connecting device according to an embodiment of the present invention. FIG. 2 is a schematic perspective view showing a configuration example in which a block and a capillary of a connecting device according to an embodiment of the present invention are fixed. 9 is a plan view showing area A in FIG. 8. FIG. FIG. 9 is a perspective view showing the shape of a fixing column member in the configuration example shown in FIG. 8; 9 is a plan view showing the shape of a block in the configuration example shown in FIG. 8. FIG. 9 is a cross-sectional view perpendicular to the thickness direction, showing the shape of the capillary of the configuration example shown in FIG. 8. FIG.

Next, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings below, the same or similar parts are designated by the same or similar symbols. However, it should be noted that the drawings are schematic and the thickness ratio of each part may differ from the actual one. Furthermore, it goes without saying that the drawings include portions with different dimensional relationships and ratios. The embodiments shown below exemplify devices and methods for embodying the technical idea of this invention. It is not specific to

The connection device according to the embodiment of the present invention shown in FIG. 1 is used for testing an optical device that has an electrical signal terminal through which an electric signal propagates and an optical signal terminal through which an optical signal propagates. Although the optical device is not particularly limited, silicon photonics chips, VCSELs, etc. can be assumed. The connection device shown in FIG. 1 includes an optical connector 100 that optically connects to an optical signal terminal of an optical device, and an electrical connector 200 that electrically connects to an electrical signal terminal of an optical device. The optical connector 100 and the electrical connector 200 are arranged close to each other at positions corresponding to the distance between the optical signal terminal and the electrical signal terminal of one optical device. When the optical connector 100 is optically connected to the optical signal terminal, an optical signal propagates between the optical signal terminal and the optical connector 100. Usually, the optical signal terminal and the optical connector 100 are optically connected to each other in a non-contact state. The timing at which the optical connector 100 is connected to the optical signal terminal and the timing at which the electrical connector 200 is connected to the electrical signal terminal may be the same or may have a time difference. In short, it is sufficient that both the optical connector 100 and the electrical connector 200 can be connected to an optical device at the same time.

The connecting device functions as a probe card that connects the testing device to the optical device to be tested. Although not shown, the optical device to be inspected is a connecting device with the surface on which optical signal terminals and electrical signal terminals (hereinafter collectively referred to as "signal terminals") are facing downward in FIG. placed opposite. When measuring an optical device, the optical connection end 101 of the optical connector 100 and the optical signal terminal of the optical device are optically connected, and the electrical connection end 201 of the electrical connector 200 is connected to the electrical signal terminal of the optical device. Connect electrically. As a result, for example, an electrical signal is input to the optical device from the electrical connection end 201 of the electrical connector 200, and an optical signal output from the optical device is input to the optical connection end 101 of the optical connector 100. , the optical signal is detected by a measuring device such as a tester (not shown).

An optical fiber or the like is preferably used for the optical connector 100. For example, an optical signal enters from an optical signal terminal of an optical device into an end face of an optical fiber arranged near the optical signal terminal. However, the optical connector 100 is not limited to an optical fiber, and any optical component having an optical waveguide can be used. All optical waveguides such as optical fibers are formed to have the same refractive index as the optical device. For example, in order to be compatible with silicon photonics devices, the optical connector on the probe card side is also formed of a material that matches the refractive index of silicon.

For the electrical connector 200, a probe made of a conductive material or the like is preferably used. For example, a cantilever type probe is used for the electrical connector 200. However, the type of probe that can be used for the electrical connector 200 is not limited to the cantilever type, and any type of probe can be used.

As shown in FIG. 1, the connection device includes a block 10 for fixing the optical connector 100 with the optical connection end 101 of the optical connector 100 exposed on the main surface (first main surface); The circuit board 20 has a circuit board 20 attached thereto. An electric circuit that is electrically connected to the electric connector 200 is formed on the circuit board 20 . A printed circuit board (PCB board) or the like is preferably used as the circuit board 20. The electrical connector 200 is installed on the circuit board 20 and electrically connected to a bonding pad 21 provided on the circuit board 20.

The bonding pad 21 is connected to a connecting terminal 23 arranged on the circuit board 20 via an electric circuit (not shown) formed on the circuit board 20. The connection terminal 23 is arranged on the main surface of the circuit board 20 opposite to the main surface on which the electrical connector 200 is installed. The connection terminal 23 is electrically connected to the inspection device.

Further, the other end of the optical connector 100 optically coupled to the optical connection end 101 through the optical waveguide is connected to an inspection device. The optical connector 100 is connected to an inspection device via a component such as an optical connector, for example. At this time, depending on the specifications of the inspection device, the optical signal may be converted into an electrical signal, or the optical signal may be input to the inspection device as it is.

The optical connector 100 and the electrical connector 200 are installed in a connection device with predetermined positional accuracy so that they can be accurately connected to the signal terminal of the optical device to be inspected during inspection. That is, when the relative positional relationship between the optical connection end 101 of the optical connector 100 and the electrical connection end 201 of the electrical connector 200 is within a predetermined range, and the connection device and the optical device are aligned, , the optical connector 100 and the electrical connector 200 accurately connect with the signal terminal of the optical device. Here, "accurately connect" means that the optical connector 100 and the electrical connector 200 are connected to the signal terminal of the optical device to be inspected so that a predetermined measurement accuracy is obtained.

Regarding the positions of the electrical connector 200 and the optical connector 100, there is an allowable range of positions (hereinafter referred to as "optimal positions") where a predetermined measurement accuracy can be obtained by connecting with the signal terminal of the optical device. The allowable range of the optimal position is a range in which a signal can be obtained with desired accuracy and intensity if the electrical connector 200 or the optical connector 100 is located within that range. This allowable range is appropriately set depending on the accuracy required for the inspection, the performance of the connector, and the like. For example, when using an optical fiber as the optical connector 100, the permissible range of the position of the optical connector 100 is set according to the numerical aperture NA of the optical fiber.

The tolerance range for the optimal position of the optical connector 100 is narrower than the tolerance range for the optimal position of the electrical connector 200. In manufacturing the connection device shown in FIG. 1, as described later, after aligning the optical connector 100 with a small tolerance, the position of the optical connector 100 is adjusted to align the electrical connector 200. I do.

In the connection device shown in FIG. 1, the optical connector 100 is fixed to the block 10 by fitting the capillary 15 into the block 10, which fixes the optical connector 100 in a penetrating state. That is, a through hole is formed in the capillary 15 with necessary positional accuracy, and the optical connector 100 inserted into this through hole is fixed. Thereby, the optical connector 100 can be installed on the block 10 with a predetermined positional accuracy.

The number of through holes formed in the capillary 15 is arbitrary. For example, if one optical device has four optical signal terminals, a capillary 15 having four through holes is prepared for each optical device. Alternatively, if one optical device has one optical signal terminal, a capillary 15 having four through holes may be prepared for each of the four optical devices.

Note that if the optical connector 100 can be placed on the block 10 with the required positional accuracy, the capillary 15 may not be used. For example, the block 10 is divided into two parts, and V-shaped grooves for arranging the optical connectors 100 are respectively formed on the mating surfaces of the divided parts. The V-shaped groove has an opening formed in the mating surface, and is formed so that the openings coincide when the divided parts are overlapped. The optical connector 100 can be fixed inside the block 10 by overlapping the two parts with the optical connector 100 arranged in the V-shaped groove. A V-shaped groove is easier to process than forming a through hole, and can have higher dimensional accuracy. Note that the V-shaped groove may be formed only in one portion of the divided block 10.

A stiffener 30 having higher rigidity than the circuit board 20 is fixed to the circuit board 20. The stiffener 30 ensures the mechanical strength of the connection device so that the circuit board 20 does not bend, and is used as a support for fixing each component of the connection device.

Further, a guide plate 60 through which the optical connector 100 passes is arranged on the first main surface of the block 10. A guide pin 70 fixed to the stiffener 30 is inserted into a through hole provided in the guide plate 60. This defines the position of the guide plate 60. The guide plate 60 is provided with an opening area so that the alignment mark 22 formed on the circuit board 20 can be visually observed. By arranging the guide plate 60 on the first main surface of the block 10, the position of the alignment mark 22 used when installing the block 10 on the circuit board 20 can be easily confirmed.

In the connection device shown in FIG. 1, the block 10 is attached to the circuit board 20 so as to be movable along the direction perpendicular to the first main surface (hereinafter referred to as the "thickness direction"). That is, the block 10 is not fixed to the circuit board 20. A gap is provided between the guide plate 60 and the circuit board 20. Therefore, the block 10 is movable in the thickness direction with respect to the stiffener 30 and the circuit board 20 fixed to the stiffener 30. Further, by providing a gap between the guide plate 60 and the circuit board 20, even if the surface of the circuit board 20 is not flat, it is possible to suppress the influence of the uneven surface on the guide plate 60.

The connection device shown in FIG. 1 includes a position adjustment mechanism 40 that adjusts the relative position of the block 10 with respect to the circuit board 20. This position adjustment mechanism 40 is composed of a plate-shaped tension spring 41 that pulls the block 10 in one direction in the thickness direction, and a plate-shaped push spring 42 that pushes the block 10 in the opposite direction to the direction in which the tension spring 41 pulls. ing. The position of the block 10 in the thickness direction is determined by the balance between the pulling force F1 by the tension spring 41 and the pushing force F2 by the push spring 42. In order to stabilize the block 10 in a predetermined position, the elastic forces of the tension spring 41 and the push spring 42 are preset.

As shown in FIG. 1, the center part of the tension spring 41 is fixed to the second main surface of the block 10 opposite to the first main surface, and both ends of the tension spring 41 are pressed against the stiffener 30 and come into elastic contact with each other. There is. More specifically, as shown in FIG. 2, the first bolt 51 passes through the center of the tension spring 41 and is fixed to the second main surface of the block 10.

On the other hand, as shown in FIG. 2, one end of the push spring 42 is fixed to the stiffener 30 by a second bolt 52, and the other end is pressed against the second main surface of the block 10 to make elastic contact. ing. The tension spring 41 and the push spring 42 are fixed to the circuit board 20 via the stiffener 30.

Note that the position of the block 10 in the thickness direction can also be finely adjusted by, for example, screwing the second bolt 52 to the stiffener 30 and adjusting the tightening method of the screw. In this way, the combination of the tension spring 41 and the push spring 42 functions as a position adjustment mechanism that moves the block 10 relative to the stiffener 30 and the circuit board 20.

A method of manufacturing the connecting device shown in FIG. 1 will be described below. In the following, a case will be described in which an optical fiber is used as the optical connector 100 and a cantilever-shaped probe is used as the electrical connector 200.

First, an optical fiber whose ends have been terminal-treated is prepared as the optical connector 100. “Terminal processing” includes lens processing, polishing, and coating stripping of the end portion to be used as the optical connection end portion 101, and processing for attaching an optical connector to the other end portion.

Then, as shown in FIG. 3, the optical connector 100 is installed on the block 10 so that the optical connection end 101 is exposed on the first main surface of the block 10. For example, a capillary 15 through which an optical connector 100 is passed is fixed to the block 10. At this time, the amount of protrusion of the optical connector 100 was adjusted so that the optical connection end 101 was exposed from the first main surface of the block 10 at a predetermined height, and the optical connector 100 was installed at a predetermined position. After confirming this, fix the capillary 15.

Next, the guide plate 60 is attached to the first main surface of the block 10. Then, the block 10 is attached to a predetermined position on the circuit board 20. For example, the block 10 is inserted into a cavity formed at a predetermined position of the circuit board 20. At this time, the block 10 is attached to the circuit board 20 while aligning using the alignment mark 22 formed on the circuit board 20 as a mark. By arranging the guide plate 60 provided with the opening area that exposes the alignment mark 22 on the block 10, the block 10 and the circuit board 20 can be easily aligned.

Then, the stiffener 30 is fixed to the circuit board 20. At this time, as shown in FIG. 4, the position of the guide plate 60 is set by the guide pin 70 fixed to the stiffener 30.

Next, as shown in FIG. 2, the tension spring 41 and the push spring 42 are attached to the block 10 and the stiffener 30. Then, the positions of the tension spring 41 and the push spring 42 are fixed. At this time, not only the position adjustment in the thickness direction but also the adjustment in the parallel direction perpendicular to the thickness direction is performed. The reference for position adjustment is the main surface of the circuit board 20.

Then, the electrical connector 200 is installed on the circuit board 20. At this time, the positioning of the electrical connector 200 is performed with reference to the position information of the optical connector 100 as described below.

First, the positional information of the optical connector 100 is analyzed, and the amount of deviation (hereinafter simply referred to as "the amount of deviation") of the position of the optical connection end 101 from a preset setting position is detected. Then, with reference to the amount of displacement of the position of the optical connection end 101, the optimal position of the electrical connection end 201 of the electrical connector 200 is calculated.

For example, predetermined set coordinates regarding the optical connection end 101 of the optical connector 100 are compared with the coordinates of the optical connection end 101 of the optical connector 100 actually installed in the block 10, and the optical connection is established. The amount of displacement in the position of the end portion 101 is detected. Then, the coordinates of the position of the electrical connection end 201 are determined so that the amount of positional deviation of the electrical connection end 201 from the predetermined set coordinates is the same as the amount of deviation of the position of the optical connection end 101. decide.

At this time, the position of the electrical connection end 201 of the electrical connector 200 may be determined by statistically processing the amount of deviation. For example, a histogram of variations in the amount of deviation is created, and the average value, variation (deviation), etc. of the amount of deviation are calculated. Then, the position of the electrical connection end 201 of the electrical connector 200 is calculated so that it is at a predetermined relative position with respect to the optical connection end 101 of the optical connector 100.

Thereafter, the electrical connector 200 is bonded to the bonding pad 21 of the circuit board 20 so that the electrical connection end portion 201 is placed at the calculated position. Through the above steps, the connection device shown in FIG. 1 is completed.

FIG. 5 shows an example of the positions of the optical connection end 101 of the optical connector 100 and the electrical connection end 201 of the electrical connector 200. In the example shown in FIG. 5, the electrical connection ends 201 of the four electrical connectors 200 are arranged to be paired with each of the optical connection ends 101 of the four optical connectors 100. As a result, for example, four optical devices having one electric signal terminal and one optical signal terminal as a pair can be tested successively or simultaneously.

In this way, it is possible to provide a connection device having an optical connector 100 and an electrical connector 200 that connect two or more optical devices to signal terminals at the same time in response to inspection of a wafer on which a plurality of optical devices are formed. can. Alternatively, an optical device having four optical signal terminals and four electrical signal terminals can be tested using four optical connectors 100 and four electrical connectors 200. As a result, optical signals from a plurality of optical devices can be collected and measured at once, so that inspection efficiency can be improved and inspection time can be shortened.

By installing the electrical connector 200 on the circuit board 20 with reference to the position information of the optical connector 100 as described above, the relative positional relationship between the optical connection end 101 and the electrical connection end 201 can be determined. It is possible to keep the position accuracy within a desired range. Thereby, the optical connector 100 and the electrical connector 200 can be simultaneously connected to the signal terminal of the optical device with high precision. As a result, accurate measurement of optical devices becomes possible.

Note that the bonding pad 21 and the alignment mark 22 are preferably formed at the same time in the same process step when forming the circuit board 20. Thereby, the accuracy of the relative position of the bonding pad 21 and the alignment mark 22 can be increased in accordance with the manufacturing accuracy of the process step. As a result, when alignment is performed using the alignment mark 22, it is possible to align with the bonding pad 21 with high precision.

In order to obtain mechanical strength of the connection device, the stiffener 30 is formed to have a certain thickness. On the other hand, if the block 10 is made thicker, it becomes difficult to arrange the optical connector 100. For this purpose, for example, as shown in FIG. 6, a recessed portion in which the block 10 is placed is formed in the stiffener 30. FIG. 6 shows an example in which four openings 300 in which the blocks 10 are respectively disposed are formed inside one recess formed in the stiffener 30. FIG. 7 shows an example in which four blocks 10 each having a guide plate 60 arranged thereon are arranged on a circuit board 20 fixed to a stiffener 30. In FIG. 7, illustrations of components such as the optical connector 100, the electrical connector 200, and the connection terminal 23 disposed on the upper surface of the circuit board 20 are omitted.

The size of each concave portion of the stiffener 30 and the number of blocks 10 arranged therein can be arbitrarily set depending on the mechanical strength required of the stiffener 30 and the size of the blocks 10. By fixing a plurality of blocks 10 to the stiffener 30, it is possible to simultaneously test a plurality of optical devices or to test a large area optical device.

Further, the capillary 15 is pressed against the block 10 and fixed by a fixing column 16 inserted between the block 10 and the capillary 15, as shown in FIGS. 8 and 9, for example. FIG. 9 is a plan view of area A in FIG. 8. The fixing column 16 has a cylindrical shape as shown in FIG. 10, and a hole into which the fixing column 16 is inserted is formed in the block 10. The fitting hole extends in the thickness direction of the block 10 parallel to the cavity into which the capillary 15 is fitted. That is, as shown in FIG. 11, a fitting hole 12 extending parallel to the cavity 11 is formed in the block 10 around the cavity 11 into which the capillary 15 is fitted. The fitting hole 12 is formed continuously along the longitudinal direction of the cavity 11, and the capillary 15 fitted into the cavity 11 and the side surface of the fixing column 16 fitted into the fitting hole 12 come into contact with each other.

FIG. 12 shows a cross-sectional view of the capillary 15 perpendicular to the thickness direction. The capillary 15 has a through hole 150 through which the optical connection end 101 passes, and a groove 151 that fits into the fixing column 16 on the side surface in the thickness direction. After fitting the capillary 15 into the cavity 11, the fixing column 16 is fitted into the fitting hole 12, thereby fixing the capillary 15 to the block 10. In the above example, the capillary 15 is fixed to the block 10 using three fixing pillars 16.

The alignment of the capillary 15 and the block 10 is performed, for example, as follows. The capillary 15 and block 10 are set in a jig and tool designed in advance so that the outer shape of the block 10 and the reference hole 152 formed in the capillary 15 fit within a predetermined accuracy. At this time, the reference hole 152 is inserted into the reference pin attached to the jig and the capillary 15 is set. Thereafter, the capillary 15 is rotated and adjusted so that the position of the optical connector 100 and the outer shape of the block 10 fall within the design tolerance range. Once the outer shape of the block 10 and the position of the optical connector 100 have been adjusted, the fixing column 16 is inserted to fix the capillary 15. Thereafter, the block 10 to which the capillary 15 is fixed is removed from the jig.

(Other embodiments)
Although the present invention has been described by way of embodiments as described above, the statements and drawings that form part of this disclosure should not be understood as limiting the present invention. Various alternative embodiments, implementations, and operational techniques will be apparent to those skilled in the art from this disclosure. That is, it goes without saying that the present invention includes various embodiments not described here.

10...Block 15...Capillary 20...Circuit board 21...Joining pad 30...Stiffener 40...Position adjustment mechanism 41...Tension spring 42...Press spring 60...Guide plate 70...Guide pin 100...Optical connector 101...Optical connection end 200...Electrical connector 201...Electrical connection end

Claims (7)

A connection device used for testing a semiconductor device having an electrical signal terminal through which an electric signal propagates and an optical signal terminal through which an optical signal propagates,
a plurality of optical connectors each comprising an optical fiber or an optical waveguide optically connected to the plurality of optical signal terminals;
a plurality of electrical connectors each forming a pair with the optical connector and electrically connected to the electrical signal terminal;
a block for fixing the optical connector in a state in which an optical connection end that optically connects to the optical signal terminal of the optical connector is exposed on a main surface;
A circuit board on which the block is mounted so as to be movable along a thickness direction perpendicular to the main surface, wherein the electrical connector is installed and an electrical circuit is electrically connected to the electrical connector. The formed circuit board;
A connection device comprising: a position adjustment mechanism that adjusts the position of the block in the thickness direction with respect to the circuit board, and adjusts the relative position of the block with respect to the circuit board. A substrate on which a plurality of the semiconductor elements are formed, further comprising the optical connector and the electric connector that respectively connect to the electric signal terminal and the optical signal terminal for two or more of the semiconductor elements at the same time. The connection device according to item 1. further comprising a capillary that is fixed in a state where the optical connector is passed through;
3. The connection device according to claim 1, wherein the capillary is fitted into the block. a fixing column that is inserted into a fitting hole extending parallel to the cavity around the cavity of the block into which the capillary is fitted, and whose side surface contacts the capillary to press and fix the capillary to the block; 4. The connecting device according to claim 3, further comprising a material. The position adjustment mechanism is
a plate-shaped tension spring that pulls the block in one direction in the thickness direction;
a plate-shaped push spring that pushes the block in a direction opposite to the pulling direction of the tension spring;
5. The connection device according to claim 1, wherein the position of the block in the thickness direction is determined by a balance between the pulling force of the tension spring and the pushing force of the push spring. further comprising a stiffener fixed to the circuit board and having higher rigidity than the circuit board,
the tension spring fixed to the block elastically contacts the stiffener;
The connection device according to claim 5, wherein the push spring fixed to the stiffener contacts the block elastically. further comprising a guide plate disposed on the main surface of the block and through which the optical connector passes;
7. The connection device according to claim 6, wherein a guide pin fixed to the stiffener is inserted into a through hole provided in the guide plate.

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