TW577989B - Probe head and method for forming probe needles on the probe head - Google Patents

Abstract

A probe head includes a substrate and a plurality of probe needles. The probe needles are formed on a surface of the substrate with a plurality of contact pads. Each probe needle comprises a metal layer and a support layer. Each support layer extends with a shape of curve and has a tip portion. The metal layers are combined on the corresponding contact pads and extend to the tip portions along the corresponding support layers. Each support layer is formed at a side surface of the corresponding metal layer. So the support layers support the metal layers elastically and increase the electrically contact of metal layer for a semiconductor wafer under test.

Description

577989 V. Description of the Invention (l) [Field of the Invention] The present invention relates to a detection head for detecting semiconductor wafers, and particularly to a detection head with elastic probes and a method for forming the elastic probes. [Previous technology] After the semiconductor wafer manufacturing is completed, it is necessary to test its electrical properties. The tester for testing semiconductor wafers usually includes a probe card, which is combined with a probe head ( pr〇be head) '$ 楝 Probe head is formed with a plurality of probes (p 『〇beneed 1 e

) 'To electrically contact the pads of the integrated circuit on the wafer. The material of the welding pad is known to be aluminum or copper. Its' surface will produce an aluminum oxide layer or a copper oxide layer', which will easily cause the probe to detect Poor electrical contact when touched.

In U.S. Patent No. 6,307,392 "Probe card and its manufacturing method, a probe card is disclosed, which includes a substrate, a lead and a contact end. The method of forming the probe card is to provide a Finger support plate 'The finger support plate is etched with a v-shaped or U-shaped groove for the formation of the contact end, and a finger layer is formed on the finger support plate, such as by sputtering A copper layer, and a substrate is provided. The substrate is conventionally formed with a detection circuit, and a connecting portion is formed at one end of the finger layer to electrically connect the substrate. Finally, the substrate is removed from the finger support plate. At this time, the index finger layer will peel off the index finger support plate, so a index finger is formed on the substrate. One end of the index finger has a V-shaped or U-shaped contact end, and the other end is electrically connected by a connecting portion. To the substrate, and the height of the connecting portion is to provide a flexible space for the fingers to make the contact end elastically contact an electronic device, however,

5. Description of the invention on page 6 (2) For the 20% method, when the substrate is moved away from the index finger support plate, the index finger ^ 柘 is formed on the index shot support plate, and the% finger layer may not be able to peel off the blade smoothly. Fingers ^ & Μ and may cause the problem of finger breakage. In addition, as for the probe structure of the probe card, 1 # FREE End formed by connecting part? / Refers to no two two ^ p. Device 'in the case of long-term use, in addition, the 5 ;, refers to L ί bends or breaks near the connection, which will cause short ^, because d, between ㈣ ⑯'Electronic devices otherwise distributed on the test pad. '" The second picking needle is less suitable for detecting high-density welding. [Objective and summary of the invention] The probe with an elastic probe contains a metal layer and a support layer. The φ, ^ ^ alder needles, each A probe system includes a tip portion, and the support layer is bent and extended. Therefore, the tip portion of the support layer of the curved centers is elastically supported, and can :::;! ::: Some layers provide a good contact. The electrical method of the two metal layers to one Feng conductor wafer is clear. The method is to first form a fj on the substrate: a probe forming method of the probe head to form a second photoresistor. A photoresist layer is patterned with a lithographic photoresist layer to form a photoresist layer on the jth floor, the supporting support surface is formed into a supporting layer, and the first and second photoresist arcs are removed to remove the first The photoresist and the _ yi; metal layer of the support layer, followed by the 支 Γ ten resistance of the elastic support, so multiple pins can be formed on a substrate at a time for power supply contact-semiconductor wafer = 577989 V. Description of the invention ( 3) pad. The probe head according to the present invention includes a substrate and a plurality of probes. The probes are formed on a surface of the substrate. The surface of the substrate is formed with a plurality of connection pads. Each probe has a metal layer. And a support layer, wherein each support layer is curved and extended and has a tip portion, one end of the metal ^ is connected to the corresponding connection pad, and the other end is extended to the tip portion of the corresponding support layer, the The support layers are formed on one side surface of the corresponding metal layer to support the metal layers. • f. The method for forming a probe of a probe according to the present invention includes the steps of: providing a substrate, such as a silicon substrate, a printed circuit board, or a ceramic substrate; a substrate, and a plurality of connection pads formed on a surface thereof; First resists are on the surface of the j substrate, the first photoresist systems do not cover the connections k and 第一 a first photoresist system has a supporting surface; a photoresist layer is formed on the two right sides ^, And lithography the photoresist layer to make the surface of the substrate i ;; a! Two photoresistors, each-the second photoresistor has-an arc-shaped supporting resistor and the first resistive layers on the surface of the substrate and covers the first light-supporting the thickness of a photoresistive branch / photoresistive layer It is formed between the 25 ~ 2 cores in the qi / Py pattern to form a plurality of supporting layers, which are the floors; the connection between the branch-shaped floor and the branch-plane of the photo-resistance. Cover, the metal layers are bonded to the second photoresist on the substrate and the support layer of i; and the first photoresist and the probe are removed. A plurality of support layers are formed with the metal layers [Detailed description of the invention]

Page 8 577989 V. Description of the invention (4) Please refer to the attached drawings. The present invention will enumerate the following embodiments: In a specific embodiment of the present invention, Figures 1 to 7 are probe heads A cross-sectional view of the method for forming the probe 120 of 100. First, as shown in FIG. 1, a substrate is provided, such as a silicon substrate, a printed circuit board (PCB), or a ceramic substrate. In this embodiment, The substrate 110 can be a silicon substrate, a ceramic substrate, a polyimide film, or a glass fiber reinforced resin (FR-4) printed circuit board. One surface of the substrate 110 can be formed. There are a plurality of connection pads 112 (contact pads), such as Cu pads or A1 pads, etc. The connection pads 11 2 can be arranged in a grid array, a central arrangement or a peripheral arrangement. Screen printing or photolithography (photo 1 thogr aphy, including exposure and development 4 processes) and other methods, 'the surface 111 of the substrate 11 is formed with a plurality of first photoresistors 20 0, these A photoresist 200 does not cover the connection pads 112 and has a support surface 210. Preferably, the support surfaces 21 and the surface 111 of the substrate 110 are approximately perpendicular to each other. In this embodiment, In the first photoresist 2 0 0 is an exposed Negative photoresist, which is not easily decomposed, is formed of a photosensitive dry film. Next, as shown in FIG. 2, a photoresist layer 300 is formed on the surface 111 of the substrate 110 by spin coating, printing, or spray coating. Preferably, The photoresist layer 300 is not covered and is slightly lower than the first photoresists 200. In this embodiment, the photoresist layer

11 ^ Page 9 577989 V. Description of the invention (5) The resist layer 300 is a positive photoresist that will decompose upon exposure. The photoresist layer 30Q lithography is imaged. The second photoresist 200 is used as a mask, and a light source (such as ultraviolet rays) is irradiated to the photoresist layer 300 to expose the photoresist layer 300. After development, the image is as shown in FIG. 3 In the figure, a plurality of second photoresistors 3 are formed on the surface 11 1 of the substrate 1 10, and the second photoresistors 310 do not cover the connection pads 112 of the substrate 11 and each The second photoresist 310 has an arc-shaped supporting surface 31m. Afterwards, as shown in FIG. 4, a support photoresist layer 400 is formed on the surface 111 of the substrate 110 by spin coating, printing, or spray coating. The support photoresist layer 400 covers the first light. Resistance 200 and the second photoresist 31. In this embodiment, the thickness of the supporting photoresist layer 400 is between 25 and 250 // m, which is a negative photoresist (negative ph〇t〇resist), and contains a high-molecular polymer (such as polyimide, phenylcyclobutene or other) with a dielectric constant and a photo-sensitive substance. As shown in FIG. 5, the photoresist layer 400 is patterned by lithography imaging technology to form a plurality of support layers 123, which are formed on the arc-shaped support surfaces 311 of the second photoresists 310 and Each supporting layer 123 extends to the supporting surface 2 10 of the first photoresist 200. Each supporting layer 123 is curved and has a tip portion 124. Preferably, one end of the supporting layer 123 is coupled to the substrate 11. The non-electrode portion of the surface 111 (that is, the portion where the connection pads 2 and 2 are not formed). Then, as shown in FIG. 6, a plurality of metal layers are formed on the substrate 110. The metal layers 121 are nickel, gold, silver, copper, or metal, which are covered with the corresponding support layer 123. One end of each metal layer 121 is bonded to the corresponding connection pad 11 2 of the substrate 110, and the other end is extended to the corresponding

IH1 Page 10 577989 V. Description of the invention (6) The branch #layer 1 2 3 and the tip 1 2 4 of the invention. Conventionally, the way to form the metal sound 121 is: 1. plating (platlng) 》》 Mineral metal layer (evaporation) or sputtering (sputtering) and other methods to form a metal cover layer (not shown) on the substrate u0, and a layer of photoresist is formed on the metal cover layer. After exposure and imaging The photoresist is located on the portion where the metal layer 121 is to be formed, and then the metal cover layer is etched to form a plurality of metal layers 121; or, a photoresist is formed on the substrate 11 (not shown) (Out) 'After exposure and development, the photoresist system has a plurality of openings, which correspond to the portion where the metal layer 121 is to be formed, and then a metal layer is formed at each opening by means of deposition or electric ore 21 After that, the photoresist is removed to form a plurality of metal layers 121 covering the corresponding support layers 23. Finally, as shown in FIG. 7, the first photoresist 200 and the second photoresist 310 are removed to form a detection head with a probe 120. The probe 120 is formed by The metal layers 121 and the support layers 123 are formed, wherein the branch floors 1 2 3 are formed on one side surface 1 2 2 of the corresponding metal layer 1 2 1 to provide good elastic support. As shown in FIG. 8, the probe head 100 of the present invention is combined with the interface card 130 of a probe card, and is electrically connected to a test device (not shown in the figure). The probes 1 2 0 of 100 are electrically contacted with a test wafer 500 to test the wafer 500. The test wafer 500 is a memory and a micro area. Wafer or microcontroller, the wafer 500 has an active surface 511 (active surface) and a non-active surface 512 (passive surface), a plurality of which are formed on the active surface 511

Page 11 577989 V. Description of the invention (7) Bonding pads 51 3 (bonding pads). During the test, the wafer under test 500 was fixed by a wafer carrier 600, and the probe head 1 The probes 120 are electrically contacted with the solder pads 513 of the wafer under test 500. Each of the probes 120 has a metal layer 121 and a support layer 123, and the metal layers are corresponding to each other. The solder pad 513, the probe is the M touch wafer 500, that is, the support layer 1 2 3 is a metal layer 121 that provides a good elasticity of the branch 120 and has a very good effect. 4 彳 木 针 金属 oxidation # "Γ is asexual, the electrical contact of circle 500 on the surface of piercing weld 513. One layer), and to improve the protection scope of the test crystal, the subject of the present invention shall prevail, Anyone familiar with this technique *, = ,: Any changes and modifications made within the scope defined by the patent scope will not depart from the spirit and scope of the present invention. /, U, belong to the protection scope of the present invention. Page 12_577989

Figure 1 according to the present invention, Figure 2 according to the present invention, Figure 3 according to the present invention, Figure 4 according to the present invention, Figure 5 according to the present invention, Figure 6 according to the present invention, Figure 7 according to the present invention, figure 8 according to the present invention, figure 8: The invention [Illustration of the drawing number] 100 probe head 110 substrate 111 surface 120 probe 121 metal layer 123 support layer 130 interface card 200 first _ photoresistor 300 photoresistor layer 400 support photoresistor layer 500 wafer 511 active surface 600 tool 'Sectional view of a substrate forming a plurality of first photoresists', Sectional view of a substrate forming a photoresistive layer;, Sectional view of a substrate forming a plurality of second photoresist's forming a sectional view of a substrate supporting the photoresistive layer; Sectional views of substrates of the plurality of support layers;, Sectional views of substrates forming the plurality of metal layers;, Sectional views of the first photoresistors and the second photoresistive probe heads; and Cross section of the test wafer 11 2 Connection pads 1 2 2 Side surface 124 Tip 210 Support surface 310 Second photoresist 311 Curved support surface 512 Non-active surface 513 Test electrode

Claims (1)

577989 6. Scope of patent application [Scope of patent application] 1. A probe head includes: a substrate 'a surface of the substrate is formed with a plurality of connection pads; and a plurality of probes, each probe system includes a A metal layer and a support layer, wherein each support layer has a tip portion, one end of the metal layer is coupled to the corresponding pad of the substrate, and the other end extends to the tip portion of the corresponding support layer, The support layers are formed on one side surface of the corresponding metal layer to support the metal layers. 2. The probe head as described in item 1 of the scope of patent application, wherein the support layers extend in a 'curved manner'. 3. The probe according to item 1 of the scope of the patent application, wherein one end of the support layers is bonded to a non-electrode portion on the surface of the substrate. 4. The detection head as described in item 1 of the scope of patent application, wherein the branches are photoresistors with a thickness between 25 and 250 // m. 5. The probe head as described in item 1 of the scope of patent application, wherein the metal layers are made of gold, silver, copper or copper. 6. The probe head as described in item i of the patent application scope, wherein the substrate is a Shi Xi substrate, a printed circuit board or a ceramic substrate. 7. A method for forming a probe of a probe head, the steps of which include: providing a substrate, one surface of the substrate is formed with a plurality of connections to form a plurality of first photoresistors on the surface of the substrate, and the first A photoresist does not cover the connection pads of the substrate, and each first photoresist has a supporting surface; 577989 The scope of the application for a patent forms a photoresist layer on the surface of the substrate; imaging the photoresist 2 lithography to form a plurality of second photoresist on the surface of the substrate, and each second photoresist has an arc-shaped support ； / Forming a supporting photoresist layer on the surface of the substrate and covering the first photoresist and the second photoresist; the cover / second opening pattern is patterned to form a plurality of supporting layers, It is the surface of the arc-shaped supporting surface of the second and second photoresistors and extends to the first photoresist to form a plurality of metal layers. The metal layers are connected with the connection pads and cover the corresponding floors; and " 4 of the substrate has a photoresist and the second photoresists to form a plurality of probes having the support layer and the metal layer. Inflammation I ... 8. The method of detecting the probe as described in item 7 of the scope of the patent application, wherein the supporting photoresist layer is patterned == one end of the layer is bonded to the non-electrode part on the surface of the substrate: the These methods include the probe head method described in the patent application No. 7, wherein the first photoresists are negative photoresists. Ten formation methods 10. The method of the probe head as described in item 7 of the scope of patent application, wherein the support surfaces of the -photoresistors and the substrate are approximately perpendicular. Surface system 11: The method as described in item 7 or 9 of the scope of patent application, wherein the second photoresists are positive photoresists. Master's slave needle formation method, in which the first-photoresist method is formed: Ten forming squares, 4th edition printing η 12, as described in item 7 of the scope of patent application, page 15 577989 (screen printing) or photolithography. 1 3. The method of the detecting head according to item 7 of the scope of patent application, wherein when the photoresist layer is lithographically imaged, the first to form a square mask and irradiate the photoresist layer with a light source. — Photoresistance is 14. The method of detecting the probe as described in item 7 of the scope of patent application, wherein the method of forming a supporting photoresistive layer is spin coating (/ square coating), printing, or spray coating. ). 15. The probe formation method of the probe head as described in the 7th worker in the scope of patent application, wherein the thickness of the supporting photoresist layer is between 25 ~ 25, and the probe head described in the 7th worker in the scope of patent application A probe forming method, in which the metal layers are formed by means of electroplating, evaporation, or sputtering. 17. For example, please ask for the method of forming a probe for a probe according to Item 7 of the patent. The towel is in the step of providing a substrate, which is a Shixi substrate, a printed circuit board, or a ceramic substrate.