A test head for a probe station

Abstract

The present invention relates to a test head for a probe station, which is used in conjunction with a carrier and a probe card, and includes a cover plate, a fixed frame, an interface board, a needle tower and a box body; a joint and a downward connection point are provided on the interface board, the connection point is electrically connected to the joint, and the interface board is fixedly installed with the fixed frame; the needle tower is installed under the fixed frame, the needle tower is provided with a pinhole, a spring pin is installed in the pinhole, the upper end of the spring pin is in contact with the connection point of the interface board, and the lower end of the spring pin is used to contact and connect with the probe of the probe card; the other end of the cover plate is flipped relative to the rotation axis to realize the closed cover state and the open cover state between the cover plate and the box body; in the closed cover state, the lower end of the spring pin of the needle tower can pass through the through hole A at the bottom of the box body to form a contact connection with the probe on the probe card. The present application can achieve reliable connection with the probe through a simple structure.

Description

Technical Field

[0001] The invention relates to the field of semiconductor design and production, and in particular to a test head for a probe station. Background Art

[0002] In the preparation of integrated circuits, wafer testing is an indispensable process. It reflects component characteristics and problems on the production line by measuring the electrical parameters of components such as resistance, capacitance, and transistors in the test keys on the wafer.

[0003] Wafer testing equipment includes a tester and a probe station (probe card). During measurement, the wafer is carried on a wafer carrier in the probe station, and is connected to the probe on the probe card through the pads of the chip on the wafer. The probe station is provided with a test head, which is stably connected to the tester through a cable, and uses the contact between the spring needles on the test head and the probes on the probe card to complete the test path for parameter measurement. Therefore, in wafer testing, the test head on the probe station plays an important role in completing the test path. The structure of the test head and the contact method between the spring needle and the probe will affect the service life of the spring needle and the probe. Both the spring needle and the probe are expensive, and frequent replacement causes economic losses. Therefore, it is urgent to optimize the structure of the test head to make the connection of the test path simple and reliable, and to ensure the service life of the spring needle and the probe. Summary of the invention

[0004] The main purpose of the present invention is to overcome the deficiencies in the prior art and provide a test head with a simple and reliable structure for a probe station. To solve the above technical problems, the solution of the present invention is:

[0005] Provided is a test head for a probe station, used in conjunction with a carrier and a probe card, comprising a cover plate, a fixing frame, an interface plate, a needle tower and a box body;

[0006] The interface board is provided with a connector and a downward connection point, the connection point is electrically connected to the connector, and the interface board is fixedly mounted on the fixed frame; the cover plate is mounted on the fixed frame, the cover plate is provided with a through hole B, so that the external cable can pass through the through hole B of the cover plate and be connected to the connector on the interface board; the needle tower is mounted under the fixed frame, the needle tower is provided with a pinhole, a spring pin is installed in the pinhole, the upper end of the spring pin is in contact with the connection point of the interface board, and the lower end of the spring pin is used to contact and connect with the probe of the probe card;

[0007] The box body is a structure with an upper end opening, and the box body is installed on a carrier carrying the probe card, and a through hole A is provided at the bottom of the box body for the probe card to be exposed upward;

[0008] One side of the box body and one side of the cover plate are connected to form a rotating axis, and the other end of the cover plate is flipped relative to the rotating axis to realize the closed state and the open state between the cover plate and the box body; in the closed state, the lower end of the spring needle of the needle tower can pass through the through hole A at the bottom of the box body to form a contact connection with the probe on the probe card.

[0009] The test head for the probe station has a simple and reliable structure. By controlling the opening and closing of the cover plate and the box body, the connection between the spring pin and the probe on the probe card can be realized, which facilitates the control of the test path.

[0010] Preferably, the test head for the probe station further comprises a gas spring, one end of which is connected to the box body, and the other end of which is connected to the cover plate, for providing support and buffering when the cover plate is turned over. The gas spring can slowly lift and lower the cover plate.

[0011] As a further improvement, a locking assembly is provided in the box body, and the cover plate and the fixed frame are flexibly connected (this connection can float, that is, the cover plate and the fixed frame can be relatively displaced); the locking assembly includes a connecting part for connecting the fixed frame and a transmission mechanism for driving the fixed frame and the interface board and the needle tower thereon to vertically rise and fall a certain distance; when the cover plate is flipped to a closed state, the spring needles on the needle tower are close to the probe card and the lower ends of the spring needles are parallel to and do not contact the probes on the probe card, and at the same time, the fixed frame is connected to the connecting part of the locking assembly, and the transmission mechanism of the locking assembly is actuated to make the lower ends of the spring needles on the needle tower contact and connect with the probes on the probe card.

[0012] The above-mentioned test head for the probe station, due to the flexible connection between the cover plate and the fixed frame, enables the fixed frame and the interface board and needle tower fixed on the fixed frame to achieve secondary lifting relative to the box body. First, it is rotated to a closed state driven by the cover plate. This is the first lifting. In this stage, the spring pins are aligned with the probes on the probe card, and the plane where the lower ends of all the spring pins are located is set horizontally. Then, the locking assembly is used to drive it to lift for the second time, so that the spring pins are in contact and connected with the probes, so that all the spring pins can contact the probes at the same time.

[0013] The test head for the probe station is equipped with a locking assembly, which optimizes the way in which the spring pins are pressed down to contact the probes on the probe card. When the cover plate covers the box body, the spring pins on the pin tower do not contact the probes on the probe card. By controlling the transmission in the locking assembly, the fixed frame, the interface board and the pin tower are moved downward as a whole, and then the spring pins are horizontally lowered to form a contact connection with the probes, ensuring that all the spring pins on the pin tower are in contact with the probes on the probe card at the same time, eliminating the problem of spring pins at different positions contacting the probes one after another when the cover plate gradually covers the box body, so that the spring pins and probes at different positions are close to the theoretical life given by the manufacturer.

[0014] As a further improvement, positioning pins are provided on a pair of side edges of the fixed frame;

[0015] The transmission mechanism includes a rotating shaft, a connecting rod, a rotating handle, a bearing, a linear guide rail and a positioning slider; there are two linear guide rails, which are symmetrically installed on both sides of the through hole A on the box body, and each linear guide rail is slidably connected with a positioning slider, namely, a positioning slider A and a positioning slider B; a slide groove is opened on one side of the positioning slider, and the slide groove includes an upper slide groove section and a lower slide groove section. The upper end of the upper slide groove section opens to the upper end surface of the positioning slider, the lower end of the upper slide groove section is connected to the upper end of the lower slide groove section and a positioning point G is provided at the connection, and a positioning point D is provided at the lower end of the lower slide groove section, and the positioning point D is lower than the positioning point G; after the two positioning sliders are respectively installed on the corresponding linear guide rails, the two positioning sliders are opened The sides of the slide groove are arranged relatively to each other; the slide groove is the connecting part in the locking assembly, and the positioning pin on the fixed frame can enter the corresponding slide groove to realize the connection. When the positioning pin is at the positioning point D, the cover plate and the box body are in a closed state, and the lower end of the spring needle on the needle tower is parallel to the probe on the probe card and does not contact each other. When the positioning pin is at the positioning point G, the lower end of the spring needle on the needle tower is in contact with the probe on the probe card. The bearings are set to two, namely bearing A and bearing B, and the two bearings are respectively mounted on the corresponding rotating shafts. Bearing A and bearing B, positioning slider A and bearing A, and positioning slider B and bearing B are all connected by connecting rods, and the rotating handle is set on bearing A.

[0016] When the cover gradually covers the box body, the positioning pins on the sides of the fixed frame can enter the corresponding slide grooves of the positioning slider respectively, and when the cover and the box body are in the closed state, each positioning pin is respectively at the positioning point G of the corresponding slide groove, so that the spring needle of the needle tower passes through the through hole A of the box body and approaches the probe card installed on the carrier, and the lower end of the spring needle and the probe card are in a state of being parallel and non-contacting with each other; at this time, the bearing A can be rotated along the rotating shaft by turning the rotating handle, driving the positioning slider A to slide along the linear guide rail, and at the same time, the bearing A drives the bearing B to rotate, and then the bearing B drives the positioning slider B to slide along the linear guide rail, and the positioning pins of the fixed frame slide from the positioning point G of the corresponding slide groove to the positioning point D respectively, so that the fixed frame, the interface board and the needle tower are moved down as a whole until the spring pins form a contact connection with the probes on the probe card; when it is necessary to open the cover, the bearing A can be rotated in the opposite direction along the rotating shaft by turning the rotating handle, so that the positioning pins of the fixed frame can slide from the positioning point D of the corresponding slide groove to the positioning point G respectively, and then the cover is opened.

[0017] The locking assembly with the above structure can achieve that all spring pins are in contact with the probes on the probe card at the same time through a simple structure.

[0018] As a further improvement, four positioning pins are symmetrically installed on a pair of side edges of the fixed frame, that is, two positioning pins are installed on one side edge, and two identical sliding grooves are correspondingly opened on one side of the positioning slide block.

[0019] As a further improvement, the test head for the probe station also includes a cable box, which is a box-shaped structure with an open bottom; the cable box is installed on a fixed frame, and the cover plate is sleeved on the cable box using a through hole B; a cable hole is opened on the cable box, so that the cable can pass through the cable hole into the cable box to achieve connection with the connector on the interface board.

[0020] As a further improvement, one side of the cover plate is connected to the box body, and a flip handle is installed on the other side for realizing a closed state and an open state between the cover plate and the box body by operating the flip handle.

[0021] As a further improvement, the fixed frame is a rectangular frame structure, and reinforcing ribs are also arranged in the rectangular frame. A corresponding through groove is opened on the interface plate, and a corresponding installation groove is opened on the needle tower. The reinforcing ribs on the fixed frame can pass through the through groove of the interface plate and then be embedded in the installation groove on the needle tower, thereby realizing a rigid connection between the fixed frame, the interface plate and the needle tower.

[0022] As a further improvement, the test head for the probe station includes a carrier, a concave circular step is provided at the center of the carrier for carrying the probe card; the test head for the probe station can be fixedly mounted on the probe station through the carrier.

[0023] As a further improvement, the test head for the probe station further includes a probe card, and the probe card is fixedly mounted on the carrier by positioning pins.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The structure of the present invention is simple and reliable. By controlling the opening and closing of the cover plate and the box body, the connection between the spring pin and the probe on the probe card can be realized, which facilitates the control of the test path.

[0026] 2. The present invention is equipped with a locking assembly, which optimizes the way in which the spring pins are pressed down to contact the probes on the probe card. When the cover plate covers the box body, the spring pins on the pin tower do not contact the probes on the probe card on the carrier. By controlling the rotating handle in the locking assembly, the fixed frame, the interface board and the pin tower are moved downward as a whole, and then the spring pins are horizontally lowered to form a contact connection with the probes, ensuring that all the spring pins on the pin tower contact the probes on the probe card at the same time, eliminating the problem that the spring pins at different positions contact the probes one after another when the cover plate gradually covers the box body, so that the spring pins and probes at different positions are close to the theoretical life given by the manufacturer. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the present invention in an open cover state.

[0028] Figure 2 It is a structural schematic diagram of the closed state of the present invention.

[0029] Figure 3 It is a cross-sectional view of the present invention in a closed state.

[0030] Figure 4 It is a top view of the present invention in a closed state.

[0031] Figure 5 It is an exploded view of the present invention.

[0032] The illustrations in the figure are marked as follows: 1. fixed frame; 2. cover plate; 3. interface board; 4. needle tower; 5. probe card; 6. box body; 7. carrier; 8. positioning pin; 9. rotating shaft; 10. connecting rod; 11. bearing A; 12. bearing B; 13. positioning slider A; 14. positioning slider B; 15. linear guide; 16. rotating handle; 17. gas spring; 18. cable; 19. flip handle; 20. cable box. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0034] like Figures 1 to 5 A test head for a probe station shown includes a cover plate 2, a cable box 20, a fixed frame 1, an interface board 3, a needle tower 4, a gas spring 17, a box body 6, a locking assembly, a carrier 7 and a probe card 5. The test head is fixedly mounted on the probe station using a carrier 7 (cardholder).

[0035] The upper plane of the interface board 3 is provided with a joint, and the lower plane of the interface board 3 is provided with a connection point; the fixed frame 1 is a rectangular frame, and a reinforcing rib is also provided in the rectangular frame, a through slot is correspondingly provided on the interface board 3, and a mounting slot is correspondingly provided on the needle tower 4, and the needle tower 4 is installed under the fixed frame 1, and the reinforcing rib on the fixed frame 1 can pass through the through slot of the interface board 3 and then be embedded in the mounting slot on the needle tower 4, so as to realize the rigid connection between the fixed frame 1, the interface board 3 and the needle tower 4. The needle tower 4 is provided with a pinhole, and a spring pin is installed in the pinhole, the upper end of the spring pin is in contact with the connection point of the interface board 3, and the lower end of the spring pin is used to contact and connect with the probe of the probe card 5. Four positioning pins 8 are symmetrically installed on a pair of side edges of the fixed frame 1, that is, two positioning pins 8 are installed on one side edge. The cable box 20 is a box-shaped structure with an opening at the bottom, which is installed on the fixed frame 1. A cable hole is provided on the cable box 20, and the cable 18 used to connect the test machine can pass through the cable hole and enter the cable box 20 to realize the connection with the joint on the interface board 3. The cover plate 2 is provided with a through hole B. The cover plate 2 is sleeved on the cable box 20 by using the through hole B and is flexibly connected to the fixed frame 1 , that is, the cover plate 2 and the fixed frame 1 can be relatively displaced.

[0036] The box body 6 is an open structure at the top, and a through hole A is formed at the bottom of the box body 6. The carrier 7 is fixed at the bottom of the box body 6, and a concave circular step for carrying the probe card 5 is provided at the center of the carrier 7. The probe card 5 can be fixedly mounted on the concave circular step by means of positioning pins to ensure that the probe card 5 is horizontally mounted on the carrier 7.

[0037] The locking assembly is installed in the box body 6, and the locking assembly includes a rotating shaft 9, a connecting rod 10, a rotating handle 16, a bearing, a linear guide 15 and a positioning slider. There are two linear guides 15, which are symmetrically installed on both sides of the through hole A in the box body 6, and each linear guide 15 is installed with a positioning slider, namely, a positioning slider A13 and a positioning slider B14; one side of the positioning slider is provided with two identical slide grooves, and the slide groove is in an "L" shape after counterclockwise rotation, including an upper slide groove section and a lower slide groove section, the upper section of the upper slide groove section opens to the upper end surface of the positioning slider, the lower end of the upper slide groove section is connected to the upper end of the lower slide groove section, and a positioning point G is provided at the connection, and a positioning point D is provided at the lower end of the lower slide groove section, and the positioning point D is lower than the positioning point G; after the positioning sliders are respectively installed on the corresponding linear guides 15, the sides of the two positioning sliders with the slide grooves are arranged opposite to each other. There are two bearings, namely bearing A11 and bearing B12, which are respectively sleeved and installed on the corresponding rotating shaft 9. The positioning slider A13 is connected to the bearing A11 through a connecting rod 10, and the positioning slider B14 is connected to the bearing B12 through a connecting rod 10. A connecting rod 10 is also installed between the bearing A11 and the bearing B12, and a rotating handle 16 is also installed on the bearing A11.

[0038] One side of the cover plate 2 is connected to one side of the box body 6, and a flip handle 19 is installed on the other side of the cover plate 2. A gas spring 17 is also installed between the cover plate 2 and the box body 6. By controlling the flip handle 19, the cover plate 2 is rotated around the side connected to the box body 6 as the axis, thereby realizing the closed state and the open state between the cover plate 2 and the box body 6.

[0039] When the cover plate 2 gradually covers the box body 6, the four positioning pins 8 on the side of the fixed frame 1 can respectively enter the corresponding slide grooves of the positioning slider, and when the cover plate 2 and the box body 6 are in the closed state, each positioning pin 8 is respectively at the positioning point G of the corresponding slide groove, so that the spring needle of the needle tower 4 passes through the through hole A of the box body 6 and approaches the probe card 5 installed on the carrier 7. At this time, the centers of the fixed frame 1, the interface board 3, the needle tower 4, the probe card 5 and the carrier 7 are all on the same straight line, and the lower end of the spring needle and the probe card 5 are in a state of being parallel to each other and not in contact. At this time, by turning the rotating handle 16, the bearing A11 is rotated along the rotating shaft 9, driving the positioning slider A13 to slide along the linear guide 15. At the same time, the bearing A11 drives the bearing B12 to rotate, and then the bearing B12 drives the positioning slider B14 to slide along the linear guide 15. The positioning pins 8 of the fixed frame 1 slide from the positioning point G of the corresponding slide groove to the positioning point D, so that the fixed frame 1, the interface board 3 and the needle tower 4 are moved down as a whole until the spring needles form a contact connection with the probes on the probe card 5.

[0040] When the cover needs to be opened, the handle 16 is turned to make the bearing A11 rotate in the opposite direction along the rotating shaft 9, so that the four positioning pins 8 of the fixed frame 1 slide from the positioning point D of the corresponding sliding groove to the positioning point G, thereby opening the cover 2.

[0041] The test head for the probe station is simple and reliable in structure, and is additionally equipped with a locking assembly, which optimizes the way in which the spring needle is pressed down to contact the probe on the probe card 5. When the cover plate 2 covers the box body 6, the spring needle on the needle tower 4 does not contact the probe of the probe card 5. By controlling the rotating handle 16 in the locking assembly, the fixed frame 1, the interface board 3 and the needle tower 4 are moved downward as a whole, and then the spring needle is horizontally lowered to form a contact connection with the probe, ensuring that all the spring needles on the needle tower 4 are in contact with the probe on the probe card 5 at the same time, eliminating the problem that the spring needles at different positions contact the probes one after another when the cover plate 2 gradually covers the box body 6, so that the spring needles and probes at different positions are close to the theoretical life given by the manufacturer.

[0042] Finally, it should be noted that the above examples are only specific embodiments of the present invention. Obviously, the present invention is not limited to the above examples, and many variations are possible. All variations that can be directly derived or associated with the content disclosed by a person skilled in the art should be considered as the protection scope of the present invention.

Claims

1. A test head for a probe station, used in conjunction with a carrier and a probe card, characterized in that: The test head for the probe station comprises a cover plate, a fixing frame, an interface plate, a needle tower and a box body; The interface board is provided with a connector and a downward connection point, the connection point is electrically connected to the connector, and the interface board is fixedly mounted on the fixed frame; the cover plate is mounted on the fixed frame, the cover plate is provided with a through hole B, so that the external cable can pass through the through hole B of the cover plate and be connected to the connector on the interface board; the needle tower is mounted under the fixed frame, the needle tower is provided with a pinhole, a spring pin is installed in the pinhole, the upper end of the spring pin is in contact with the connection point of the interface board, and the lower end of the spring pin is used to contact and connect with the probe of the probe card; The fixed frame is a frame structure, and a reinforcing rib is also arranged in the frame. A through slot is correspondingly opened on the interface plate, and a mounting slot is correspondingly opened on the needle tower. The reinforcing rib on the fixed frame can pass through the through slot of the interface plate and then be embedded in the mounting slot on the needle tower, thereby realizing a rigid connection between the fixed frame, the interface plate and the needle tower; The box body is a structure with an upper end opening, and the box body is installed on a carrier carrying the probe card, and a through hole A is provided at the bottom of the box body for the probe card to be exposed upward; One side of the box body and one side of the cover plate are connected to form a rotation axis, and the other end of the cover plate is flipped relative to the rotation axis to realize the closed state and open state between the cover plate and the box body; in the closed state, the lower end of the spring pin of the needle tower can pass through the through hole A at the bottom of the box body to form a contact connection with the probe on the probe card; A locking assembly is provided in the box body, and the cover plate and the fixed frame are flexibly connected so as to be able to move relative to each other; the locking assembly comprises a connecting portion for connecting the fixed frame and a transmission mechanism for driving the fixed frame and the interface board and the needle tower thereon to vertically rise and fall a certain distance; when the cover plate is flipped to a closed state, the spring needles on the needle tower are close to the probe card and the lower ends of the spring needles are parallel to and do not contact the probes on the probe card, and at the same time, the fixed frame is connected to the connecting portion of the locking assembly, and the transmission mechanism of the locking assembly is actuated to make the lower ends of the spring needles on the needle tower contact and connect with the probes on the probe card.

2. A test head for a probe station according to claim 1, characterized in that: The test head for the probe station also includes a gas spring, one end of which is connected to the box body, and the other end of which is connected to the cover plate, so as to provide support and buffer when the cover plate is turned over.

3. A test head for a probe station according to claim 1, characterized in that: A pair of side edges of the fixed frame are provided with positioning pins; The transmission mechanism includes a rotating shaft, a connecting rod, a rotating handle, a bearing, a linear guide rail and a positioning slider; there are two linear guide rails, which are symmetrically installed on both sides of the through hole A on the box body, and each linear guide rail is slidably connected with a positioning slider, namely, a positioning slider A and a positioning slider B; a slide groove is opened on one side of the positioning slider, and the slide groove includes an upper slide groove section and a lower slide groove section. The upper end of the upper slide groove section opens to the upper end surface of the positioning slider, the lower end of the upper slide groove section is connected to the upper end of the lower slide groove section and a positioning point G is provided at the connection, and a positioning point D is provided at the lower end of the lower slide groove section, and the positioning point D is lower than the positioning point G; after the two positioning sliders are respectively installed on the corresponding linear guide rails, the two positioning sliders are opened. The sides with the slide groove are arranged opposite to each other; the slide groove is the connecting part in the locking assembly, and the positioning pin on the fixed frame can enter the corresponding slide groove to realize the connection. When the positioning pin is at the positioning point D, the cover plate and the box body are in a closed state, and the lower end of the spring needle on the needle tower is parallel to the probe on the probe card and does not contact each other. When the positioning pin is at the positioning point G, the lower end of the spring needle on the needle tower is in contact with the probe on the probe card. The bearings are set to two, namely bearing A and bearing B, and the two bearings are respectively mounted on the corresponding rotating shafts. The bearing A and the bearing B, the positioning slider A and the bearing A, and the positioning slider B and the bearing B are all connected by connecting rods, and the rotating handle is set on the bearing.

4. A test head for a probe station according to claim 3, characterized in that: Four positioning pins are symmetrically installed on a pair of side edges of the fixed frame, that is, two positioning pins are installed on one side edge, and two identical sliding grooves are correspondingly opened on one side of the positioning sliding block.

5. A test head for a probe station according to claim 1, characterized in that: The test head for the probe station also includes a cable box, which is a box-shaped structure with an opening at the bottom; the cable box is installed on a fixed frame; the cover plate is sleeved on the cable box using a through hole B; a cable hole is opened on the cable box, so that the cable can pass through the cable hole into the cable box to achieve connection with the connector on the interface board.

6. A test head for a probe station according to claim 1, characterized in that: One side of the cover plate is connected to the box body, and the other side is provided with a flip handle, which is used to realize a closed state and an open state between the cover plate and the box body by operating the flip handle.

7. A test head for a probe station according to any one of claims 1 to 6, characterized in that: The test head for the probe station comprises a carrier, the center of which is provided with a concave circular step for carrying a probe card; the test head for the probe station can be fixedly installed on the probe station through the carrier.

8. A test head for a probe station according to claim 7, characterized in that: The test head for the probe station also includes a probe card, and the probe card is fixedly mounted on the carrier through positioning pins.

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