TW436627B - Test fixture for a ball-type semiconductor package - Google Patents

Abstract

A kind of test fixture used for electrical measurement of ball-type semiconductor package includes a test board and a ground loop bar. Plural openings and an electrically conductive layer are allowed to use for the test board so as to accomplish the purpose that ball body can touch semiconductor package near the test board surface. The ground loop bar is placed at a test board to provide extension for test probe and ground terminal. The test fixture also provides accurate short and open compensation to compensate the parasitic effects among the test probe, substrate and ground loop bar. The test fixture can be calibrated by the calibrator of conventional frequency-domain instrument. The test fixture is easily operated and the manufacturing material is inexpensive. The test fixture can be used for the electrical measurement of the solder ball having different pitches.

Description

'436627 V. Description of the invention (1) Field of the invention The present invention relates to a test fixture for electrical measurement of semiconductor devices. In particular, it is a test for measuring electrical properties of ball-type semiconductor devices. BACKGROUND OF THE INVENTION A typical spherical device, such as a bal id array (BGA) device. Small conductive members act as a medium for connection. For example, ball-shaped solder balls (solder bal 1) are often used in the construction of spherical grid arrays. This type of welded kick ball may have a small diameter size, only about 0.3 a centimeter (mm) to 1. 2 7 mm. In the final assembly, the solder balls are usually arranged in an array that is both delicate and dense. The circuitry in this configuration is also quite dense. There are several problems when testing the spherical grid array configuration because of the density kick. One problem is that the solder balls are placed separately and at very small distances. Therefore, it can be understood that for a test fixture, it is a difficult operation to fix these desired solder balls for testing.

C: \ patent \ 870090erso. Ptd page 4 436627 5. Description of the invention (2) Another problem is that the use of a calibrator and a test probe (test pr0be) constructed in a spherical grid array, also has It is very small ^ inch ', so it is easily damaged. In addition, this test fixture is also possible: calibration is not easy. Because solder balls are placed separately and at different distances, different test fixtures are needed to handle the different pitches between the balls. This requires the purchase of a variety of different test fixtures, thus increasing the cost of purchasing measurement equipment.

SUMMARY OF THE INVENTION The present invention overcomes the shortcomings of the above-mentioned conventional test fixtures, electrical structures', such as spherical structures, when testing highly dense. , Mingzhi-The purpose is to provide a test fixture with a spherical configuration for electrical measurement. This test fixture can be used to effectively fix the desired object when testing. It is easy to operate and it is easy to operate. The measured data is also more stable. Yet another object of the present invention is to shake you ^, and n & μ to provide a test fixture, this test fixture can use the traditional frequency domain instrument (.1 w1equity-domain instrument) standard corrector, cup „you γ, ^ a ^ ^ If an open, short, or load (1 oad) corrector is used, the object is used as the electrical measurement of the spherical structure.

436627 V. Description of the invention (3 ~~ '----- use. A further object of the present invention is to provide a kind of test fixture. The manufacturing material of this test fixture is quite cheap, and it is easy to use solder balls with different pitches. . Therefore 'can help the test fixture to measure in different pitch solder balls.% Wang In a preferred embodiment, the test fixture of the present invention includes: a ground loop bar (ground 100p bar) to provide The test probe, the extension of the ground terminal, and a test board provided with a ceramic substrate, the ceramic substrate provides a sphere 'contact with the semiconductor structure in the opening of the test board. A plurality of spaced-apart openings are formed on the substrate, and a plurality of spaced-apart openings formed on the Taumann substrate are used to insert a test probe into a test fixture to communicate with solder balls. According to the present invention, an 'electrically conductive layer' is attached to the ceramic substrate and is interposed between the semiconductor structure and the ceramic substrate. By contacting the electrically conductive layer, The test probe can be connected to the ground. The present invention also provides accurate short-circuit and open-circuit compensation to compensate for parasitic effects between the test probe, the substrate, and the ground return rod. With the following drawings, detailed description of the embodiment and patent application

436627

V. Description of the Invention (4) The above and other objects and advantages of the present invention are described in detail below. Brief Description of the Drawings Fig. 1 is a plan view illustrating a test pole of a test fixture according to an embodiment of the present invention. Section 2 is a cross-sectional view illustrating a test fixture according to an embodiment of the present invention. The test fixture is assembled in a spherical grid array. FIG. 3 is a drawing A illustrating one of the ground return rods 201 in FIG. 2. FIG. 4 illustrates an enlarged cross-sectional view of one of the test boards in FIG. 2. FIG. 5 illustrates how the test probe is short-circuit compensated according to the present invention. FIG. 6 illustrates how the test probe is compensated for open circuit according to the present invention. The detailed convergence of the preferred embodiment of the present invention # In the following description, a magnified expression is provided to facilitate the description of the present invention. Reference circle 1 is a cross-section of a test panel 100 according to the present invention. The test panel 100 includes a base plate m on which a plurality of divided openings 110 are formed. Around the M substrate 1G1 are multiple branches

43S627 V. Description of the invention (5) ---, 02 1G9. As shown in FIG. 2, the test fixture is fixed on a spherical structure through the teeth of the eight branches at the ends i G2˜109. Fig. 2 illustrates a cross-sectional view of a test fixture 200. According to the embodiment of Fig. 2, the test fixture is placed in a solder ball array. As shown in FIG. 2, the test device 200 includes a test board 100 including a ceramic substrate 100 and a ground return rod 2101, which is located on the test board 101. Supplied to test probe, extension of ground terminal. As shown in FIG. 丨, the test probe 200 in the test fixture 200 contacts the solder ball 204 through the opening 110 formed in the ceramic substrate 101. With the support of multiple supporting pins, this test fixture 200 is fixed on this spherical structure. The supporting pin of the tip Figure 3 illustrates an enlarged view of the ground loop rod 201, as shown by circle 3, and the ground loop rod 201 includes a contact The ground terminal 301 'is provided to provide the test probe 304 in close contact with the ground. The ground return rod 201 is generally made of metal. The test probe 304 includes a coaxial cable (coaxiai cable) and a metal-coated outer layer. The ground return bar 201 also includes a rectangular bar 302 ', and a central opening 303 is formed in the rectangular bar 302. When the test probe 304 is activated ', this test probe is scanned via a central opening 303 formed in the ground return rod 201. The present invention allows the test probe 304 to multiply along the object under test during the test.

C: \ patent \ 870090erso. Ptd page 8 436627 5. Description of the invention (6) 'Dimension (nmlti-dimensionai) movement. As shown in Figure 3, during test 3 + 04, you can move toward or away from the object, or you can move in Shanghai. In a single-scanning period, multi-dimensional movement: the first occurrence is, on the surface of the spherical lattice structure, along the test plate. This allows the test probe 30 to electrically contact the conductive member, such as solder, to form an opening 11 1 on the test board 100. FIG. 4 is an enlarged cross-sectional view of the test board 1000 in FIG. 2. As shown in FIG. 4, the inner surface (inner Mace) of the opening 11 () formed on the ceramic substrate 101 is covered with a conductive material, and a thin conductive buffer layer 401 may be formed by Made of pressure conductive rubber (PCR). A plurality of openings 402 are formed in the buffer layer 401 to expose solder balls 204. The pressure conductive rubber layer 401 serves as an electrically conductive medium to be contained on the test board. The contact with the solder ball is completed in the opening. As shown in FIG. 2, the test probe is inserted into the opening of the test board, and the conductive material touching the inner surface of the opening 11 is contacted with the solder ball. 'Because the conductive material is electrically contacted to the solder ball 204 with a buffer layer of 40u. As a result, the electrical contact can occur intermittently between the test probe and the ground. A Electrical conductivity is normally proportional to The vertical stress of the test probe is vertical conduction and the test platform is not parallel. The buffer layer 401 can use a metal conductive plate.

C: \ patent \ 870090erso. Ptd page 9 436627 V. Description of the invention (7) A thin layer of pressure-conducting rubber can provide light and better electrical conductivity for testing. In the preferred embodiment, the thickness of the two rooms is about 0,5 feet. From Figure 4, it can be seen that Fu: Rubber is a small conductive member. They may have only about 0.77mm ^^, the balls are straight ten, // 7, and are located at extremely small distances, such as 27 mm. The solder ball is exposed through an opening formed in the ceramic substrate. The interval between the openings hPM i ng) is determined in advance according to the different pitches between the solder balls.

The openings are formed in a number of different designs. Regardless of the form or arrangement of the openings, it is necessary to maintain high-precision adjustment with the test probes. ^ The parasitic effects between the test probes, the ceramic substrate and the ground return rod can occur in very small conductive components, such as solder balls. During the test. The test fixture of the present invention also provides a mechanism that can accurately compensate for the effects of parasitics in an effective and low-cost manner. To compensate for this parasitic effect, the pressure conducting rubber layer is removed from the test board and a metal plate, such as a copper plate, is inserted, and the substrate of the test board of the present invention is attached. Fig. 5 and Fig. 6 respectively illustrate how to complete short circuit and open circuit compensation for a test probe according to the present invention. Referring to FIG. 5, a test board provided with a copper plate 502 makes all solder balls of the object to be tested in contact with the copper plate 502 for short-circuit compensation, and these objects to be tested are connected to the ground terminal β through this contact This design 'tests probes,

436627 V. Description of the invention (8)

Investigate the parasitic effects in the base plate and ground return pole to compensate. Referring to FIG. 6 ′, only the welding record of the object under test tested by the test probe is not in contact with the copper plate 502 for open circuit compensation. Parasitic effects in test probes, ceramic substrates, and ground return rods are therefore compensated. The only ones described above are only the preferred embodiments of the present invention. When = this can limit the scope of implementation of the present invention D, that is, all equal changes and modifications made in accordance with the present invention in the scope of patents should still belong to the present invention. The scope of invention patents.

C: \ patent \ 870090erso. Ptd p. 11

No. 081112053 Patent Application No. 43662? Explanation of component symbols 100 test board 101 ceramic substrate 110 Opening Printed by the Ministry of Economic Affairs Central Building Standard Bureau 8 Industrial Welfare Committee 102 ~ 109 support last 200 test fixture 201 grounded Circuit rod 203 test probe 204 contact solder ball 301 contact ground terminal 304 test probe 302 rectangular rod 303 center opening 401 conductive buffer layer 402 opening 502 copper plate This paper is applicable to China® Home Standard (CNS) A4 specification (2 丨0X297 male

Claims (1)

436627 Sixth, the scope of patent application 1. = Testing fixture for electrical measurement of spherical semi-conductor Zhao structure, including. A test board, the test board contains a number of bases and a ground loop bar contacting the opening, placed接地 _ ^. _, Λ, B ^ ^ ^ on the test board, the ground loop has a central opening; and, a test probe, the test probe is provided with a test pin, and passes through the center. An opening is inserted into the one contact opening, and two ^ ^ ^ M ^ contacts a conductive sphere formed on the spherical semiconductor structure; wherein the test fixture is fixed on the spherical semiconductor structure to allow the Multi-dimensional movement of the test probe on the spherical semiconductor structure 6 2 · The test fixture for the electrical measurement of the spherical semiconductor structure as described in item I of the scope of patent application 'The ground loop rod further includes A ground terminal to provide electrical ground to the test probe. 3. The test fixture for electrical measurement of spherical semiconductor structures as described in item 1 of the scope of the patent application, the ground loop rod is electrically conductive. 4. As described in Item 1 of the scope of the patent application, the test fixture for measuring the properties of spherical semiconductor structures is supported by a plurality of supports. Not much electricity 5, as used in spherical semiconductor fabrication as described in the first patent application C: \ patent \ 870090erso.ptd p. 12 436627 ^ The measuring test fixture, wherein the contact opening is provided with a predetermined interval, and the predetermined interval is determined in advance by a distance between conductive spheres formed on the spherical semiconductor structure. • The test fixture for electrical measurement of spherical semiconductor structures as described in item 1 of the scope of patent application, the substrate is a ceramic substrate. 7. The test jig for electrical measurement of a spherical semiconductor structure as described in item 1 of the scope of the patent application, the contact opening is provided with an inner surface covered with an electrically conductive material. 8. The test fixture for electrical measurement of spherical semiconductor structures as described in item 7 of the scope of the patent application, the test board further includes a contact layer attached to the bottom surface of the test board to provide the inside Electrical contact between the surface and the conductive sphere constructed by the spherical semiconductor. 9. The test fixture for electrical measurement of spherical semiconductor structures as described in item 8 of the scope of patent application, the contact layer is a pressure-conductive rubber layer. According to the test fixture for electrical measurement of spherical semiconductor structures described in the patent application No. 8 item, the contact layer is an electrically conductive sheet. 11. The test fixture for electrical measurement of spherical semiconductor structures according to item ίο of the scope of application for patents, wherein the conductive sheet is connected to be 436627 6. Scope of patent application '' The conductive sphere to be tested and other conductive spheres to ground tested by this test probe are compensated for short-circuit by parasitic effects in the test probe, ceramic substrate and ground return rod. 12. The test fixture for electrical measurement of a spherical semiconductor structure as described in item 10 of the scope of the patent application, wherein the conductive sheet connects all conductive spheres to ground except for those to be tested by the test probe. The measurement of the conducting ball's body is open-circuit compensated for parasitic effects in the test probe, ceramic substrate and ground return rod. C: \ patent \ 870090erso.ptd p. 14