Wafer Test System

Abstract

To provide a wafer test system that improves usage efficiency.SOLUTION: A wafer test system includes a wafer test cassette, a carrier stage, and a test device. The wafer test cassette comprises a first magnetic member. The carrier stage comprises a second magnetic member, and the wafer test cassette is secured to the carrier stage by magnetic attractive forces generated between the first magnetic member and the second magnetic member. The test device comprises a test host and a test cabinet, the test cabinet includes a test space and is for housing the wafer test cassette and the carrier stage, and the test host is electrically connected to the wafer test cassette.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a wafer test system, and more particularly to a wafer test system in which a wafer test cassette is fixed by a magnetic attraction structure. [Background technology]

[0002] After a wafer has completed the integrated circuit design, the wafer must undergo a pre-burn test and an electrical test. Conventionally, for the pre-burn and reliability tests, each wafer is individually tested using a test host and a probe card. Each wafer is placed on a carrier stage and electrically contacted with the probes of the probe card to perform the test. Therefore, the more wafers there are, the more test hosts and probe cards are required, which increases the time and equipment costs.

[0003] In order to improve the efficiency of pre-burn tests, a multi-test unit system capable of simultaneously pre-burning multiple wafers has been developed. In such a system, multiple test unit arrays are installed in a single test device, and each wafer is placed in its own test unit array. Each test unit has at least one cassette for fixing the wafer, and the pre-burning test or electrical test is performed through a test host.

[0004] Recently, a new type of wafer test cassette has been developed in which a probe card and wafer are pre-positioned and placed in the wafer test cassette, electrically connected directly to a test host, and placed in a test unit for pre-burn or electrical testing. The upper and lower housings of existing wafer test cassettes are connected using either a cationic or vacuum method. The cationic method has limited effectiveness in connecting and securing the upper and lower housings, leading to problems such as uneven force distribution and deformation.

[0005] Therefore, how to improve the utilization efficiency of the test system through structural design improvements and overcome the above-mentioned deficiencies is one of the important issues that the project aims to solve. Summary of the Invention [Problem to be solved by the invention]

[0006] The technical problem that the present invention aims to solve is to provide a test system with a magnetic attraction and fastening structure in response to the shortcomings of existing technology. [Means for solving the problem]

[0007] The test system includes a wafer test cassette and a test device. The wafer test cassette has a first magnetic member and at least one first electrical contact. The test device includes a test host and at least one test cabinet. The test cabinet has a test space and a second electrical contact. The carrier stage has a second magnetic member and is installed at a test position in the test space. The test space is used to accommodate the wafer test cassette. The second electrical contact of the test cabinet is electrically connected to the first electrical contact of the wafer test cassette so as to electrically connect the test host to the wafer test cassette. The wafer test cassette is fixed to the carrier stage by a magnetic attraction force generated between the first magnetic member and the second magnetic member. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram illustrating a test system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram illustrating the test cabinet of the embodiment shown in FIG. 1. [Figure 3] FIG. 2 is a schematic diagram showing a wafer test cassette according to the embodiment shown in FIG. 1. [Figure 4] 1 is a schematic diagram showing a wafer test cassette according to an embodiment of the present invention; [Figure 5]1 is a schematic diagram showing a wafer test cassette according to an embodiment of the present invention; [Figure 6] 1 is a schematic diagram illustrating a test system according to an embodiment of the present invention. [Figure 7] 1 is an illustration showing the relationship between a wafer test cassette and a test space according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] Please refer to Figures 1 to 3. Figure 1 is a schematic diagram showing a test system according to an embodiment of the present invention. Figure 2 is a schematic diagram showing a test cabinet according to the embodiment shown in Figure 1. Figure 3 is a schematic diagram showing a wafer test cassette according to the embodiment shown in Figure 1.

[0010] In this embodiment, the test system SYS1 includes at least a wafer test cassette 1A, a carrier stage SB, and a test device TE1. The wafer test cassette 1A is movably mounted on the carrier stage SB. A probe card 112 is mounted in the wafer test cassette 1A, and the probe card 112 includes one or more probes 1121. During the test process, the probes 1121 contact the solder pads 131 of the wafer 13, and the probes 1121 are in electrical contact with the solder pads of the wafer 13.

[0011] Please refer to Figures 1 and 2. In this embodiment, the test device TE1 has a test host TE11 and a test cabinet TE12, and the test cabinet TE12 includes multiple test spaces TS (TS1-TS25). Each test space TS is used to accommodate a wafer test cassette 1A. A carrier stage SB is located at a test position in the test space TS.

[0012] In this embodiment, the wafer test cassette 1A includes a first housing 11 and a second housing 12. In some embodiments, the first housing 11 and the second housing 12 are tightly coupled to each other by engagement or vacuum. In some embodiments, the first housing 11 and the second housing 12 are tightly coupled to each other by magnetic attraction. See the description below for details.

[0013] The wafer test cassette 1A is movably mounted on the carrier stage SB. The wafer test cassette 1A includes a first magnetic member 111. In this embodiment, the first magnetic member 111 can be mounted in the first housing 11 or the second housing 12, but is mounted in the first housing 11 in this embodiment. The carrier stage SB also includes a second magnetic member SB-P. The wafer test cassette 1A is fixed to the carrier stage SB by a magnetic attraction force generated between the first magnetic member 111 and the second magnetic member SB-P. The carrier stage SB and the wafer test cassette 1A are arranged to perform a test process within the test space TS. The first magnetic member 111 and the second magnetic member SB-P are not limited to permanent magnets; one may be a magnetically conductive material and the other a paramagnetic element (an electromagnet or a permanent magnet).

[0014] The wafer test cassette 1A includes a first electrical contact 118, which is electrically connectable to a second electrical contact SEP of the test cabinet TE12 to electrically connect the test host TE11 to the wafer test cassette 1A. In this embodiment, the first electrical contact 118 is located in the second enclosure 12. In some other embodiments, the first electrical contact 118 is located in the first enclosure 11, although the present invention is not limited thereto. When the wafer test cassette 1A is located in the test space TS, the first electrical contact 118 in the first enclosure 11 or the second enclosure 12 is electrically connected to the second electrical contact SEP of the test device TE1. This allows the test device TE1 to perform a test process on the wafer 13 in the wafer test cassette 1A. In this embodiment, the first electrical contact 118 is located in the extension 12E of the second enclosure 12 and is in electrical contact with the second electrical contact SEP.

[0015] According to one embodiment, the electrical connection between the test host TE11 and the wafer test cassette 1A is established simultaneously with, before or after the magnetic attraction force is generated.

[0016] According to one embodiment, the first housing 11 and the second housing 12 are closely coupled to each other. For example, if a first magnetic member 111 is installed in one of the first housing 11 and the second housing 12 and a third magnetic member 121 is installed in the other, when the first housing 11 and the second housing 12 approach each other, an attractive magnetic force is generated by the first magnetic member 111 and the third magnetic member 121, causing the first housing 11 and the second housing 12 to be closely coupled to each other. In this embodiment, the wafer test cassette 1A includes two pairs of the first magnetic member 111 and the third magnetic member 121. When the first housing 11 and the second housing 12 approach each other, the wafer test cassette 1A is closely coupled to and fixed in place by the attractive magnetic force generated by the first magnetic member 111 and the third magnetic member 121.

[0017] According to an embodiment, the first magnetic member 111 and the third magnetic member 121 may each be a paramagnetic material, such as a permanent magnet, a non-permanent magnet, or a non-magnetic conductive material. The non-magnetic conductive material may be, for example, but not limited to, iron, cobalt, or nickel. In this embodiment, the non-permanent magnet is an electromagnet.

[0018] According to one embodiment, the carrier stage SB includes a magnetic barrier assembly SB-B, which is arranged to reduce or eliminate the magnetic attractive force between the first magnetic member 111 and the second magnetic member SB-P. If the magnetic attractive force is always present between the wafer test cassette 1A and the carrier stage SB when they approach each other, it becomes difficult to apply sufficient force when placing the wafer test cassette 1A on the carrier stage SB, which may result in damage to the wafers 13 and the probe card 112 in the wafer test cassette 1A. Therefore, the magnetic barrier assembly SB-B is installed to eliminate or reduce the magnetic attractive force, and after the wafer test cassette 1A is placed on the carrier stage SB, the wafer test cassette 1A is again fixed to the carrier stage SB by the magnetic attractive force.

[0019] In this embodiment shown in FIG. 3 , the magnetic barrier assembly SB-B is a movable shield that shields the second magnetic member SB-P to eliminate or reduce the magnetic attraction between the first magnetic member 111 and the second magnetic member SB-P. After the wafer test cassette 1A is placed on the carrier stage SB, the magnetic barrier assembly SB-B is separated from the second magnetic member SB-P, and the magnetic attraction between the second magnetic member SB-P and the first magnetic member 111 is generated or strengthened, securing the wafer test cassette 1A to the carrier stage SB. Also, in some embodiments, it is the second magnetic member SB-P that is movable, and the second magnetic member SB-P is made of a magnetically conductive material, such as iron, nickel, or cobalt, and can also be a permanent magnet. Before the wafer test cassette 1A is placed on the carrier stage SB, the second magnetic member SB-P is moved to the magnetic barrier assembly SB-B and shielded by the magnetic barrier assembly SB-B. When the wafer test cassette 1A is placed on the carrier stage SB, no magnetic attraction force is generated between the first magnetic member 111 and the second magnetic member SB-P, but after the wafer test cassette 1A is placed on the carrier stage SB, the second magnetic member SB-P is separated from the magnetic barrier assembly SB-B and released from shielding by the magnetic barrier assembly SB-B, and a magnetic attraction force is generated between the first magnetic member 111 and the wafer test cassette 1A, locking and fixing the wafer test cassette 1A to the carrier stage SB.

[0020] Please refer to FIG. 4. FIG. 4 is a schematic diagram showing a wafer test cassette 1B according to an embodiment of the present invention. In this embodiment, the first electrical contact 118 and the second electrical contact SEP of the wafer test cassette 1B are connected by magnetic attraction. For example, the test cabinet TE12 has a magnetic object ME disposed on one side of the second electrical contact SEP, corresponding to the third magnetic member 121. The magnetic object ME may be a paramagnetic element or may have an opposite polarity to the third magnetic member 121. In this manner, the first electrical contact 118 and the second electrical contact SEP are electrically connected by the magnetic attraction between the magnetic object ME and the third magnetic member 121. However, the present invention is not limited thereto. Alternatively, the first electrical contact 118 and the second electrical contact SEP may be electrically connected by magnetic attraction between two magnetic elements disposed on one side of the first electrical contact 118 (in the wafer test cassette) and one side of the second electrical contact SEP (on the test cabinet).

[0021] Please refer to FIG. 5. FIG. 5 is a schematic diagram showing a wafer test cassette 1C according to an embodiment of the present invention. According to one embodiment, the second magnetic member SB-P is an electromagnet and has a magnetic region. The magnetic barrier assembly SB-B includes a power supply P and a switch and is connected to the electromagnet SB-P. When the wafer test cassette 1C is placed on the carrier stage SB, the switch is turned on, and the magnetic region of the electromagnet SB-P generates a magnetic force, magnetically attracting the first magnetic member 111 and the third magnetic member 121, and magnetically locking the wafer test cassette 1C to the carrier stage SB. The switch is opened and closed under the control of a control circuit CRT.

[0022] In one embodiment, the test cabinet TE12 further includes a rail assembly (not shown) connected to the carrier stage SB. The rail assembly allows the carrier stage SB to move into or out of the test space TS. In one embodiment, the test system allows for manual placement of the wafer test cassette on the carrier stage SB, and the design of the rail assembly makes manual placement more convenient (e.g., accurately positioning the wafer test cassette opposite the carrier stage SB). However, the present invention is not limited in this respect, and in one embodiment, the test system also allows for automated processing.

[0023] Furthermore, in one embodiment, the carrier stage SB is a rail assembly, which is, for example, a component including two rail supports (not shown), one on each side of the bottom of the wafer test cassette. The two rail supports support the wafer test cassette and hold it aerial within the test space. That is, the wafer test cassette is spaced apart from the bottom (bottom wall) of the test space.

[0024] Please refer to FIG. 3 again. According to one embodiment, the wafer test cassette 1A includes a first positioning portion 11P, and the carrier stage SB includes a second positioning portion SB-F corresponding to the first positioning portion 11P. The second positioning portion SB-F is used to abut against the first positioning portion 11P. As shown in FIG. 3, the first housing 11 includes the first positioning portion 11P (a concave structure, e.g., a groove). The carrier stage SB includes a second positioning portion SB-F (a convex structure, e.g., similar to a convex rib) that protrudes upward. The first positioning portion 11P (concave structure) and the second positioning portion SB-F (convex structure) can abut against each other, thereby positioning the wafer test cassette 1A and the carrier stage SB relative to each other. Furthermore, in this embodiment, the first housing 11 includes a first convex portion 11F, and the second housing 12 includes a second convex portion 12F. The first protrusion 11F and the second protrusion 12F are installed correspondingly, and the design of the first protrusion 11F and the second protrusion 12F ensures precise alignment when the first housing 11 and the second housing 12 are joined, and the aforementioned magnetic attraction force allows the first housing 11 and the second housing 12 to be joined even more closely.

[0025] See FIG. 6. The present invention also provides a test system, which includes a wafer test cassette 1D and a test device TE2. The wafer test cassette 1D includes a first magnetic member 111. The test device TE2 includes a test host TE21 and a test cabinet TE22. The test cabinet TE22 has a test space TS for accommodating the wafer test cassette 1D. The test space TS is defined by a top plate 21, a bottom plate 23, and a sidewall 22. A second magnetic member SB-P is installed in the test space TS. In this embodiment, the second magnetic member SB-P is installed on the bottom plate 23. The wafer test cassette 1D is fixed in the test space TS and electrically connected to the test host TE21 by a magnetic attraction force generated between the first magnetic member 111 and the second magnetic member SB-P.

[0026] In this embodiment, the wafer test cassette 1D includes a first electrical contact 118, which is electrically connectable with a second electrical contact SEP of the test cabinet TE22. According to this embodiment, the first electrical contact 118 is located in the extension 12P of the second enclosure 12. When the wafer test cassette 1D is in the test space TS, the first electrical contact 118 is electrically connected with the second electrical contact SEP of the test device TE2. In this way, the test device TE2 executes a test program on the wafers 13 in the wafer test cassette 1D.

[0027] Please refer to FIG. 7, which is a schematic diagram showing a wafer test cassette 1E according to an embodiment of the present invention. In this embodiment, the first electrical contact 118 and the second electrical contact SEP of the wafer test cassette 1E are connected by magnetic attraction. For example, the test cabinet TE22 includes a magnetic object ME installed on the side wall 22, located on one side of the second electrical contact SEP. The magnetic object ME corresponds to the third magnetic member 121, which may be a paramagnetic element or have an opposite polarity to that of the third magnetic member 121. In this way, the first electrical contact 118 and the second electrical contact SEP are electrically connected by the magnetic attraction between the magnetic object ME and the third magnetic member 121. However, the present invention is not limited thereto. Two mutually attractive magnetic elements may also be installed, one on one of the first electrical contacts 118 (inside the wafer test cassette) and the other on one of the second electrical contacts SEP on the top plate 21, side wall 22, or bottom plate 23. In this way, the electrical connection between the first electrical contact 118 and the second electrical contact SEP can be achieved by the magnetic attraction between the two.

[0028] The quantity and positions of the first magnetic member 111, the second magnetic member SB-P and the third magnetic member 121 can be adjusted according to actual needs, and are not limited thereto in the present invention.

[0029] [Beneficial Effects of the Embodiments] One beneficial effect of the present invention is that the test system and wafer test method provided by the present invention can effectively improve the efficiency of wafer testing, and utilize a magnetic structure to connect the test device and the wafer test cassette, thereby effectively controlling the test environment. [Explanation of symbols]

[0030] CRT control circuit SYS1-SYS2 test system 1A-1E Wafer test cassette 11 First enclosure 11P First positioning part 11F First protrusion 111 First magnetic member 112 Probe Card 1121 Probe 118 First electrical contact 12 Second enclosure 12E Extension part 12F Second protrusion 12P extension part 121 Third magnetic member SB Career Stage SB-P Second magnetic member SB-B Magnetic Barrier Assembly SB-F Second positioning part SEP Second electrical contact 13 wafers 131 solder pad 21 Top plate 22 Side wall 23 Bottom plate TE1, TE2 test devices TE11, TE21 test host TE12, TE22 Test Cabinets TS Test Space TS1-TS25 test space

Claims

1. a wafer test cassette including a first magnetic member and at least one first electrical contact; a test device including a test host, at least one test cabinet, and a carrier stage; A wafer test system comprising: The test cabinet includes a test space and a second electrical contact, and the carrier stage includes a second magnetic member and is installed at a test position in the test space. the test space is for accommodating the wafer test cassette; the second electrical contacts electrically connect with the first electrical contacts for electrically connecting the test host to the wafer test cassette; the wafer test cassette is fixed on the carrier stage by a magnetic attraction force generated between the first magnetic member and the second magnetic member; Wafer test system.

2. the electrical connection between the test host and the wafer test cassette is established simultaneously with, before, or after the magnetic attraction force is generated; 2. The wafer test system according to claim 1.

3. the carrier stage or the wafer test cassette includes a magnetic barrier assembly, the magnetic barrier assembly being configured to reduce or eliminate the magnetic attractive force; 2. The wafer test system according to claim 1.

4. the wafer test cassette includes an extension, and the first electrical contact is located on the extension.

2. The wafer test system according to claim 1.

5. The first electrical contact and the second electrical contact are connected by magnetic attraction.

2. The wafer test system according to claim 1.

6. the test cabinet further includes a rail assembly connected to the carrier stage, the rail assembly enabling the carrier stage to move into and out of the test space; 2. The wafer test system according to claim 1.

7. the carrier stage is a rail assembly, positioned on both sides of the bottom of the wafer test cassette, and supporting the wafer test cassette; 2. The wafer test system according to claim 1.

8. the wafer test cassette includes at least one first positioning portion, the carrier stage includes at least one second positioning portion corresponding to the at least one first positioning portion, and the at least one second positioning portion is used to come into contact with the first positioning portion; 2. The wafer test system according to claim 1.

9. the wafer test cassette includes a first housing and a second housing, the first housing and the second housing being closely coupled; 2. The wafer test system according to claim 1.

10. a wafer test cassette including a first magnetic member and at least one first electrical contact; a test device including a test host and at least one test cabinet; A wafer test system comprising: Each test cabinet includes a test space and a second electrical contact; the test space is used to accommodate the wafer test cassette; the test space is defined by a top plate, a bottom plate, and a side wall, a second magnetic member is installed in the test space, the second magnetic member is installed on the bottom plate or the side wall, and the wafer test cassette is fixed to a carrier stage by a magnetic attractive force generated between the first magnetic member and the second magnetic member; the second electrical contacts of the test cabinet electrically connect with the first electrical contacts of the wafer test cassette to electrically connect the wafer test cassette with the test host; Wafer test system.

11. the electrical connection between the test host and the wafer test cassette is established simultaneously with, before, or after the magnetic attraction force is generated; The wafer test system of claim 10.

12. a magnetic barrier assembly is further installed in the wafer test cassette or the test space, and is configured to reduce or eliminate the magnetic attractive force; The wafer test system of claim 10.

13. the wafer test cassette includes an extension, and the first electrical contact is located on the extension. The wafer test system of claim 10.

14. The first electrical contact and the second electrical contact are connected by magnetic attraction. The wafer test system of claim 10.

15. the wafer test cassette includes at least one first positioning portion, and at least one of the top plate, the bottom plate, and the side wall includes at least one second positioning portion corresponding to the at least one first positioning portion, and the at least one second positioning portion is used to come into contact with the first positioning portion; The wafer test system of claim 10.

16. the wafer test cassette includes a first housing and a second housing, the first housing and the second housing being closely coupled; The wafer test system of claim 10.

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