CN111653499A

CN111653499A - Wafer test head

Info

Publication number: CN111653499A
Application number: CN202010548978.7A
Authority: CN
Inventors: 阙石男
Original assignee: Suzhou Aifangxindong Automation Equipment Co Ltd
Current assignee: Suzhou Aifangxindong Automation Equipment Co Ltd
Priority date: 2020-06-16
Filing date: 2020-06-16
Publication date: 2020-09-11

Abstract

The invention discloses a wafer test head, comprising: the base is internally provided with an optical channel and an air channel, the bottom of the base is provided with a contact pad, the air channel is communicated with the optical channel and can generate negative pressure suction, the contact pad is provided with a window, and the window is an outlet of the optical channel; the light source is arranged in the seat body and projects light to the window in a way of facing the light channel; the base body is contacted with the chip by the contact pad, so as to achieve the purposes of picking and placing the chip, applying pressure and providing light to the chip during testing.

Description

Wafer test head

Technical Field

The invention belongs to the technical field of wafer test, and particularly relates to a taking and placing pressurizing mechanism used in high-speed image sensing wafer test.

Background

Nowadays, digital image technology is continuously innovated and changed, and digital camera carriers such as digital cameras and mobile phones are miniaturized, so as to meet the requirement, the image sensing chip of the optical system is not limited to use two types of photosensitive coupling devices (CCD) or Complementary Metal-oxide semiconductor (CMOS) sensors. However, with the continuous advance of technology, the requirements of zooming by hundreds of times, hundreds of millions of pixels and shooting 8K films can be met only by relying on a COMS high-speed image sensor chip.

Before the high-speed image sensor chip is shipped, a series of tests are performed, in which a light source is provided to make the light-sensitive area obtain the required light type and intensity for performing the related tests. Generally, the transferring and carrying action of the wafer can be achieved only by using two groups of mechanisms of taking and placing and pressurizing, wherein the taking and placing mechanism is responsible for taking the wafer to move and then placing the wafer on the test needle seat; the pressure mechanism is provided with a light source for pressing the chip to ensure electrical contact with the test socket and simultaneously providing light source for testing the chip. However, the disadvantages of this approach are: 1. only two groups of mechanisms for taking, placing and pressurizing are needed, and two groups of transfer mechanisms for driving the mechanisms to move are needed, so that the mechanisms are too complex and high in manufacturing cost; 2. the operation time is too long, and the process comprises that the wafer is moved into the test needle seat, the pick-and-place mechanism is withdrawn, the pressurizing mechanism is moved into the pressure and provides the light source for testing, and the pressurizing mechanism is withdrawn. In terms of test cost, the working time is lengthened and the test amount is reduced. And the manufacturing cost of the equipment with complex structure is high. The present inventors have therefore devised an improved method for designing such a wafer test head.

Disclosure of Invention

The main objective of the present invention is to provide a chip testing head, which mainly allows the chip testing head to have the functions of sucking, pressurizing and supplying light source, so that the chip is moved to the testing socket each time, and then the light source is synchronously supplied and the pressurized contact test is performed, thereby reducing the operation time, increasing the testing efficiency, increasing the testing amount, and increasing the profit of manufacturers.

To achieve the above object, the present invention provides a wafer test head, comprising: the base is internally provided with an optical channel and an air channel, the bottom of the base is provided with a contact pad, the air channel is communicated with the optical channel and can generate negative pressure suction, the contact pad is provided with a window, and the window is an outlet of the optical channel; the light source is arranged in the seat body and projects light to the window in a way of facing the light channel; the base body is contacted with the chip to be tested through the contact pad, so as to achieve the purposes of taking and placing the chip to be tested, applying pressure and providing light to the chip to be tested during testing.

In the preferred embodiment of the present invention, the outer wall of the contact pad has a plurality of positioning bumps, the middle of the plurality of positioning bumps is the position of the window, and the plurality of positioning bumps correspond to the outline of the wafer to be tested.

In a preferred embodiment of the present invention, the base is formed by sequentially connecting and fixing the first body, the second body, the third body and the fourth body in series.

In a preferred embodiment of the present invention, the optical channel is disposed through the first mechanism, the second mechanism and the third mechanism, and the air channel is distributed in the second mechanism, the third mechanism and the fourth mechanism.

In a preferred embodiment of the invention, the air passage is in communication with the light passage at the second body.

In a preferred embodiment of the present invention, a light equalizing plate is embedded in the second housing facing the outer wall of the third housing, and the light equalizing plate is located in the path of the light channel.

In a preferred embodiment of the present invention, the light source is a circuit board having a light emitting diode, the circuit board is fixed to the third body and seals the light channel, the light emitting diode faces the light channel and can project light to the window

In a preferred embodiment of the present invention, two sets of symmetrical quick release assemblies are disposed on the outer walls of the second body and the third body, thereby facilitating the replacement of the light equalizing plate.

In summary, the present invention is a wafer test head, which has the following advantages:

1. the prior art needs two mechanisms originally, and the wafer is moved into the test needle seat, the pick-and-place mechanism is withdrawn, the pressurizing mechanism is moved into the pressurizing mechanism to provide the processes of light source test, the pressurizing mechanism is withdrawn and the like in sequence;

2. the components are simplified, the mechanism configuration in the machine table is easier, and the manufacturing cost of equipment can be saved;

3. for the test operation of the high-speed image sensing chip, the mechanism can meet the required test efficiency.

Drawings

Fig. 1 is a perspective view of the present invention.

Fig. 2 is a schematic cross-sectional view of the AA plane of fig. 1.

Fig. 3 is an exploded view of the first embodiment of the present invention.

Fig. 4 is an exploded view of the second embodiment of the present invention.

FIG. 5 is a schematic diagram illustrating the operation of the present invention.

Wherein, each reference number and its corresponding element or component name in the figure are:

1: seat body, 11: light channel, 12: the air passage is arranged on the air duct,

121: gas source inlet and outlet, 13: the contact pads, 131, the windows,

14: homogeneous plate, 15: first body, 16: a second machine body, a first machine body and a second machine body,

161: groove, 17: third body, 18: the fourth machine body

19: quick release assembly, 191: fastener, 192: the hook piece is arranged on the front end of the hook piece,

2: light source, 21: circuit board, 22: a light-emitting diode is provided,

23: auxiliary plate, 3: wafer to be tested, 4: and (6) testing the needle seat.

Detailed Description

The technical solution of the present invention will be clearly and completely described below with reference to the specific embodiments and the accompanying drawings. It will be understood that when an element is referred to as being "mounted on" or "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. In the illustrated embodiment, the directions indicate that up, down, left, right, front, rear, and the like are relative, and are used to explain that the structures and movements of the various components are relative in this case. These representations are appropriate when the components are in the positions shown in the figures. However, if the description of the location of an element changes, it is believed that these representations will change accordingly.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Fig. 1 and fig. 2 are a perspective view and a cross-sectional view of a wafer test head according to the present invention. The invention relates to a wafer test head, which comprises a base body 1 and a light source 2 arranged inside the base body.

The base 1 is responsible for picking and placing a wafer 3 to be tested and pressurizing during testing. The base 1 has an optical channel 11 and an air channel 12. The air passage 12 is communicated with the optical channel 11 and can be connected with external air supply equipment, so that negative pressure suction is generated between the air passage 12 and the optical channel 11 at proper time. The bottom of the base 1 is provided with a contact pad 13, the contact pad 13 has a window 131, and the window 131 is also an outlet of the optical channel 11. The contact pad 13 is used to contact and press the wafer 3 to be tested, and the contact pads are tightly sealed when contacting, so as to generate negative pressure when the air channel 12 is subsequently pumped, thereby adsorbing the wafer 3 to be tested. The light source 2 is disposed in the base 1 and is a circuit board 21 having a light emitting diode 22. The light source 2 is supplied with power required for operation from the outside. The light source 2 facing the light channel 11 can project light to the window 131, so that the high-speed image sensor chip as the wafer 3 to be tested can obtain the required light source during testing. The design of the invention is that the single seat body 1 can achieve the purposes of picking, placing, pressurizing and providing light sources for the wafer 3 to be tested, thereby shortening the time required by testing, improving the testing efficiency and meeting the testing requirements of the high-speed image sensing wafer.

Furthermore, for the convenience of assembly and use, the base 1 of the present invention is designed into a plurality of sets of components to facilitate the convenience of assembly and use, and then the purpose and structure of each component design will be described in detail:

as shown in fig. 3 and 4, in the embodiment, the seat 1 is formed by sequentially connecting and fixing the first body 15, the second body 16, the third body 17 and the fourth body 18 in series. In order to prevent the position from being wrong during the butt joint, the first body 15, the second body 16 and the third body 17 have first positioning holes 51 and second positioning holes 52 with different sizes on the outer walls to be butted, and the diameter of the first positioning hole 51 is larger than that of the second positioning hole 52. Similarly, the second body 16, the third body 17 and the fourth body 18 are provided with a first positioning pin 61 and a second positioning pin 62 having opposite sizes on the outer walls thereof, the size of the first positioning pin 61 is larger than that of the second positioning pin 62, the first positioning pin 61 is located in the first positioning hole 51 during assembly, and the second positioning pin 62 is located in the second positioning hole 52. The relative position of each component is ensured, and installation errors can be avoided.

The optical channel 11 is disposed through the first mechanism 15, the second body 16 and the third mechanism 17. The second body 16 has a groove 161 on a wall surface facing the third body 17. The recess 161 is provided for placement of a replaceable light homogenizing plate 14. The light homogenizing plate 14 is located in the path of the light channel 11 to homogenize the intensity of the light passing through. After assembly, the first body 15 and the second body 16 are locked together, and the third body 17 and the fourth body 18 are locked at one side. Two symmetrically arranged quick release assemblies 19 are disposed on the outer walls of the second body 16 and the third body 17. The quick release assembly 19 is only one embodiment of the present invention, and is not limited to this manner. The quick release assembly 19 includes: a fastener 191 disposed on the third body 17; a hook 192 is disposed on the second body 16. The purpose is to quickly separate the second body 16 and the third body 17 for testing and changing the light equalizing plate 14.

The light source 2 is composed of a circuit board 21 and a light emitting diode 22 disposed thereon. The circuit board 22 may also be locked to the side wall of the third body 17 by an auxiliary board 23 and close the light channel 11. Wherein the LED 22 is disposed to face the light channel 11, and the light generated by the LED 22 is projected to the window 131 through the light channel 11. Wherein the auxiliary plate 23 also helps to let the circuit board 21 seal the light channel 11.

The air passage 12 is communicated and distributed in the second body 16, the third body 17 and the fourth body 18. The air passage 12 is connected with the light passage 11 in a radial direction in the second body 16. In this embodiment, an air source inlet/outlet 121 is disposed on the fourth body 18. The gas source inlet/outlet 121 is a gas supply port of the gas duct 12, but is not limited to this. In addition, the air passage 12 is formed by drilling 1-2 holes in different directions and then partially sealing the holes by screws 122, so that the purpose of changing the direction of the air passage 12 is achieved. In addition, the outer walls of the second body 16 and the third body 17 at the position of the air passage 12 are provided with sealing rings 123, so that the bodies can be butted to each other to achieve a good sealing effect.

The contact pad 13 is disposed at the first body 15 for contacting the wafer 3 to be tested. The protruding shape of the first body 15 at the contact pad 13 corresponds to the mating test socket 4. The contact pad 13 may be made of engineering rubber and plastic, has a suitable hardness, and can ensure sealing when contacting the wafer 3 to be tested, but will not scratch the surface. In addition, the outer wall of the contact pad 13 has a plurality of positioning bumps 132. The middle of the positioning bumps 132 is the position of the window 131, the positioning bumps 132 correspond to the outline of the wafer 3 to be tested, and the size of the wafer 3 to be tested is larger than that of the window 131, so that the wafer 3 to be tested can be more easily adsorbed and cannot move randomly.

As shown in fig. 5, in the operation of such a structure, the base body 1 first moves to the storage location of the wafer 3 to be tested, when the base body 1 descends, the contact pad 13 contacts the wafer 3 to be tested, then the air channel 12 generates a negative pressure, and the optical channel 11 connected to the air channel also generates a negative pressure, so that the wafer 3 to be tested is adsorbed outside the window 131 of the contact pad 13. Then the seat body 1 is driven by other mechanisms to move to the test needle seat 4. The seat body 1 descends to enable the wafer 3 to be tested to be placed on the test needle seat 4, and further the electric contact point at the bottom of the wafer 3 to be tested is pressed down to be contacted with the probe on the test needle seat 4, at the moment, the light source 2 in the seat body 1 generates light, the light is projected to the photosensitive area at the top of the wafer 3 to be tested through the window 131, and then relevant tests can be carried out. After the test, the base body 1 moves the chip 3 to be tested to the storage area of good or bad products according to the test result, and after the chip reaches the positioning, the air duct 12 will supply air from outside in a small amount, so that the chip 3 to be tested can be smoothly placed in the storage area without the contact pad 13.

In summary, the wafer test head of the present invention has the optical channel 11 and the air channel 12 disposed on the base 1, and the air channel 12 is communicated with the optical channel 11, so that the optical channel 11 can generate the negative pressure at the proper time to suck the wafer 3 to be tested at the contact pad 13 in addition to the light source 2 irradiating the light, thereby the single base 1 of the present invention can satisfy the requirements of picking, placing, pressurizing and providing the light source for the wafer 3 to be tested, can shorten the test operation time, enhance the test efficiency and increase the profit, and the mechanism is simplified and can reduce the cost.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the embodiment of the present invention. But all equivalent changes and modifications made according to the claims of the present invention are covered by the claims of the present invention.

Claims

1. A wafer test head, comprising:

the base is internally provided with an optical channel and an air channel, the bottom of the base is provided with a contact pad, the air channel is communicated with the optical channel and can generate negative pressure suction, and the contact pad is provided with a window which is an outlet of the optical channel; and

a light source, which is arranged in the seat body and projects light to the window by facing the light channel.

2. The wafer test head as claimed in claim 1, wherein the contact pad is configured to contact a wafer to be tested, the wafer to be tested has a size larger than the window, the outer wall of the contact pad has a plurality of positioning bumps, the window is located among the positioning bumps, and the positioning bumps correspond to the outline of the wafer to be tested.

3. The wafer test head of claim 1 wherein the base is formed by a first body, a second body, a third body and a fourth body sequentially connected in series.

4. The wafer test head as recited in claim 2, wherein the optical channel is disposed through the first mechanism, the second body and the third mechanism, and the air channel is disposed in the second body, the third body and the fourth body.

5. The wafer test head of claim 2 wherein the air channel is in communication with the optical channel at the second body.

6. The wafer test head as recited in claim 2, wherein the second body is embedded with a light equalizing plate facing the outer wall of the third body, the light equalizing plate being located in the path of the light channel.

7. The wafer test head as recited in claim 2, wherein the light source is a circuit board having a light emitting diode, the circuit board is fixed to the third body and encloses the light channel, the light emitting diode faces the light channel and projects light to the window.

8. The wafer test head as recited in claim 2, wherein the fourth body has a gas source inlet and outlet, the gas source inlet and outlet being a gas supply port of the gas channel.

9. The wafer test head of claim 2 wherein the second body and the third body have two sets of symmetrical quick release members on their outer walls.