KR101465343B1 - Method of fabricating a needle for probe card and the same thereof - Google Patents

Abstract

The present invention relates to a method for fabricating a needle for a probe card. The purpose of the present invention is to facilitate the method for fabricating a needle for a probe card and to provide a simplified process. The method for fabricating a needle for a probe card according to an embodiment of the present invention comprises the following steps of: preparing a metal substrate whose surface is processed; patterning a photoresist on the substrate; forming a metal plated layer on a region where the photoresist has not been patterned using electroplating; removing the photoresist after forming the metal plated layer; coating a photosensitive film on the substrate and the metal plated layer after the photoresist; applying tape on the photosensitive film; and detaching the substrate.

Description

TECHNICAL FIELD [0001] The present invention relates to a method for manufacturing a needle for a probe card, and a needle for a probe card manufactured by the method.

The present invention relates to a method of manufacturing a probe card needle, in order to ensure the ease of manufacturing a probe card needle and to provide a simplified process.

Generally, a semiconductor device is fabricated through a fabrication process for forming a pattern on a wafer and an assembly process for assembling a patterned wafer into each device.

The semiconductor device subjected to the fabrication process is subjected to Electrical Die Sorting (hereinafter referred to as 'EDS') process for examining electrical characteristics of each device formed on the wafer before the assembly process.

Here, the EDS process is a process performed to identify a defective device among the devices formed on the wafer. In the EDS process, an inspection device is mainly used in which an electrical signal is applied to an element on a wafer and an electrical signal responded from the element is analyzed to determine whether the element is defective.

A probe card is used to transmit an electrical signal between the test equipment that determines whether the device is defective and the pad of the device. The probe card has one or more needles. The needles are brought into contact with pads connected to elements on the wafer. The semiconductor device testing device judges whether the device is defective by exchanging electric signals with the pad of the device through the needles of the probe card.

This EDS process is a process performed to discriminate defective chips among the chips constituting the wafer. In addition to selecting the defective chips and the amount of chips constituting the wafer, repairing the repairable chips among the defective chips, This is done for early feedback on problems in the process or for cost reduction in assembly and inspection by premature removal of defective chips.

Basic elements of the EDS include a tester system, a prober system, a probe card, and a tester program. Among them, a probe card is a very thin needle fixed to a printed circuit board. The generated signal is transmitted to the needles of the probe card through the performance substrate and the needle is brought into contact with the pad of the chip in the wafer to transfer the electric signal to the circuit inside the device. The failure is judged by the signal that is generated.

The probe card needle used for the EDS process is a tip of tungsten material and has epoxy type and blade type.

On the other hand, as semiconductor devices have become highly integrated and extremely miniaturized, the design rule of the pattern becomes finer. The sizes of the pads of the wafer die, in which the needles of the probe card are contacted as the semiconductor elements are miniaturized, are miniaturized.

In the conventional method of forming needles of a probe card, a needle for a probe card is manufactured by forming a metal layer using a sputter on a silicon wafer, patterning using electroless plating, PR removal, and an etching process.

More specifically, according to a conventional method, a metal layer is formed as a seed layer for plating on a silicon wafer, patterning is performed using PR (photoresist), electroplating is performed to form a needle for a probe card And the metal layer used as the seed layer was removed through etching to remove the needles. At this time, there was a problem that the needles did not fall off well in the seed layer, and in some cases, the silicon wafer existing under the plating layer was also etched.

The need for a seed layer using a seed layer according to the prior art has a problem that a sputtering process is necessarily required at the time of forming a seed layer, which requires a lot of cost and time. In addition, etching the silicon wafer in some cases complicates the process, There was a problem to be abandoned.

In addition, there has been a problem that it is not easy to store and transport the separated needles after separating the needles from the seed layer or the silicon wafer.

It is an object of the present invention to solve the problems of the prior art and to simplify the process, and to save time and cost by simplifying and simplifying the needle forming process of the probe card.

A method of manufacturing a probe card needle according to an embodiment of the present invention includes: preparing a surface-treated metal substrate; Patterning a photoresist on the substrate; Forming a metal plating layer on the portion where the photoresist is not patterned using electroplating; Removing the photoresist after forming the metal plating layer; Coating the photosensitive film on the substrate and the metal plating layer after removing the photoresist; Applying a tape onto the photosensitive film; And removing the substrate.

In this case, the surface-treated metal substrate is a metal substrate having reduced wettability or a surface-roughened metal substrate.

In this case, the wetting angle of the metal substrate with reduced wettability is preferably 70 to 80 degrees, and the surface roughness is preferably 200 to 300 nm.

The step of removing the photoresist is characterized by using acetone and IPA (isopropyl alcohol).

Meanwhile, after removing the substrate, the photosensitive film is removed using acetone to separate the plated metal layer from the tape, thereby obtaining a professional card needle.

Using the method of forming a probe card according to the present invention, a vacuum process such as a sputtering process according to the prior art is omitted, which simplifies the process and saves time and cost.

In addition, since the substrate can be recycled, there is an advantage that it is possible to solve the problem that the wafer can not be reused by etching the wafer as in the prior art.

1 is a flow chart of a method for manufacturing a probe card needle according to the prior art.
2A-2E disclose a method for manufacturing a needle for a probe card according to the prior art.
3 is a flowchart of a method for manufacturing a probe card needle according to an embodiment of the present invention.
4A-4H are schematic views of a method for fabricating a needle for a probe card according to an embodiment of the present invention.
Various embodiments are now described with reference to the drawings, wherein like reference numerals are used throughout the drawings to refer to like elements. For purposes of explanation, various descriptions are set forth herein to provide an understanding of the present invention. It is evident, however, that such embodiments may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing the embodiments.

The following description provides a simplified description of one or more embodiments in order to provide a basic understanding of embodiments of the invention. This section is not a comprehensive overview of all possible embodiments and is not intended to identify key elements or to cover the scope of all embodiments of all elements. Its sole purpose is to present the concept of one or more embodiments in a simplified form as a prelude to the more detailed description that is presented later.

2A-2E disclose a method for manufacturing a needle for a probe card according to the prior art.

According to the prior art, a needle for a probe card includes a step (S 110) of forming a metal seed layer on a wafer to which an adhesive layer is attached, as in FIG. 1; Patterning a photoresist (PR) on the metal seed layer (S 120); Forming a metal plating layer (needle) (S 130); Removing the photoresist (S 140); And etching the metal seed layer (S 150). Each step corresponds to Figs. 2A-2E.

According to this conventional technique, there is a problem that the needle (metal plating layer) does not fall off well in the seed layer, and in some cases, the silicon wafer existing under the plating layer is also etched.

Further, in the needle forming method using the seed layer according to the prior art, a sputtering process is necessarily required at the step of forming the metal seed layer at step S 110, which has a problem in that it takes a lot of time and cost.

In addition, there is a problem in that the process is complicated by etching the silicon wafer in some cases, and the silicon wafer can not be reused and must be discarded. In this case, when the wafer is etched, it takes about 24 hours and the process time is very long.

In addition, there has been a problem that it is not easy to store and transport the separated needles after separating the needles from the seed layer or the silicon wafer.

In order to solve such a problem, a method of manufacturing a probe card needle using the method as shown in FIG. 3 will be described.

A method of manufacturing a probe card needle according to the present invention includes: preparing a surface-treated metal substrate (S 310); Patterning (S 320) a photoresist on the substrate; A step (S 330) of forming a metal plating layer on the portion where the photoresist is not patterned by using electroplating; Removing the photoresist after forming the metal plating layer (S 340); Coating the photosensitive film on the substrate and the metal plating layer after removing the photoresist (S 350); Applying a tape onto the photosensitive film (S 360); And removing the substrate (S 370).

Figures 4A-4H show schematic diagrams of a method for making needles for a probe card according to an embodiment of the present invention, Figures 4A-4G correspond to steps S 310 to S 370, respectively. Hereinafter, each step will be described in detail.

1. Preparing a surface-treated metal substrate (S 310)

The substrate must be a metallic substrate. In the prior art, since a silicon wafer is used, an adhesion layer (a Ti layer is used as an adhesive layer in FIG. 2) is formed on a silicon wafer for electrolytic plating, and then a metal seed layer However, in the present invention, a metal seed layer for electrolytic plating is not separately required by using a metallic substrate.

Therefore, as in the prior art, the sputtering process, which is a vacuum process, is omitted in order to raise the metal seed layer, thereby reducing time and cost.

However, since the metal seed layer does not exist separately, the surface of the metal substrate according to the present invention must be treated.

Means that the wettability of the surface of the portion to be electroplated is low or the surface is treated to have an appropriate roughness so that the electroplating can be efficiently performed.

When the wettability is low, the wetting angle is preferably 70 to 80 degrees, and the surface roughness is preferably 200 to 300 nm. This is because if the wetting angle is too low or the surface roughness is too low, the film formation will be poor. In order to adjust the wetting angle or the surface roughness, polishing can be performed using a sandpaper.

2. Patterning the photoresist on the substrate (S 320)

A process for patterning a photoresist on a surface-treated metal substrate, and there is no particular limitation on the photoresist to be used.

3. A step (S 330) of forming a metal plating layer on a portion where the photoresist is not patterned by electrolytic plating,

Electroplating is performed by a conventional method, and the metal plating layer is plated in a plating solution. The plating solution used is preferably a NiCo plating solution. A metal plating layer made by such a metal plating is used as a probe card needle.

4. Removing the photoresist after forming the metal plating layer (S 340)

After the metal plating layer is formed, the photoresist is removed using acetone and IPA (isopropyl alcohol). In this case, as shown in FIG. 4d, the acetone used to remove the photoresist stays on the pattern wall (the acetone remains small in FIG. 4D), and this remaining acetone is then removed when the photosensitive film DFR is coated DFR linkage is broken. Therefore, if the substrate is removed as in step S 370, the DFR around the pattern wall is also detached.

5. Step (S 350) of coating the photosensitive film on the substrate and the metal plating layer after removing the photoresist,

4E, a photosensitive film (DFR) is coated on the metal and metal plating layers. There is no particular limitation on the type of the photosensitive film to be used.

6. Step of applying a tape onto the photosensitive film (S 360)

There is no particular restriction on the type of tapes used to apply the tape over the DFR. These tapes serve to facilitate storage and transport of the needles for the probe card. As shown in FIG. 4G, when the substrate is peeled off, the structure of the metal plating layer (needle) / DFR / tape is left, and transfer and storage are easy in this state. When using the needle while keeping it in this state, finally remove the DFR as in S 380 and use the needle.

7. Removing the substrate (S 370)

Finally, the substrate is peeled off. In this case, since the bonding force between the DFR and the metal plating layer is larger than the bonding force between the metal plating layer and the substrate, the substrate can be easily separated from the metal plating layer. The separated substrate is recyclable because it is not removed by etching as in the prior art.

8. Step of obtaining needle for probe card (S 380)

The DFR is removed when the needle for the probe card is actually used while storing and transporting in the state shown in FIG. 4G. DFR can be removed with acetone. By removing DFR, needle for probe card can be used immediately.

Hereinafter, the present invention will be further described with specific examples.

An SUS substrate polished using a sand paper was prepared. The wetting angle and surface roughness of the substrate were found to be about 75 degrees and the surface roughness was 200 to 300 nm.

A substrate surface-treated as described above is prepared, and a photoresist is placed on the substrate using a photoresist. The photoresist used was PMER N-, CA 3000PM, Tokyo Ohka Kogyo Co., and a photoresist was applied through a two step process (10 sec / 500 rpm - 25 sec / 2500 rpm) using a spin coater to raise the photoresist on the substrate. Lt; / RTI >

Then, an exposure time was performed for 42 seconds for patterning, and a development process was performed using P-7G to form a pattern on the substrate. The PR diversity used was CPD - BD (TMAH 2.38%) (Digicon Concept Korea) and the development time was 4min 30sec.

A metal plating layer was formed using electrolytic plating. In this case, a NiCo plating solution was used as the plating solution, and the plating solution was plated at 1.5 mA / cm for 10 minutes. Acetone and IPA were then used to remove the photoresist.

After removal of the photoresist, a photosensitive film (DFR, Dry Film Resist) was laminated, wherein the DFR used was RY-3625, Hitachi Chemical with a thickness of 25 nm. Taping was applied on it and the used tape was PI tape.

The needle for a probe card according to one embodiment of the present invention thus fabricated is made of needle / DFR / tape, and DFR existing between layers can be easily removed by using acetone. Depending on the type of pattern, it can be removed in about 10 seconds. The needle for a probe card manufactured according to the prior art has a problem that it takes about 24 hours to process the wafer when the needle is not easily kneaded and the wafer can not be reused. However, when manufactured according to the present invention, , The needle can be easily and quickly removed from the DFR.

The description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features presented herein.

Claims (6)

Preparing a surface-treated metal substrate;
Patterning a photoresist on the substrate;
Forming a metal plating layer on the portion where the photoresist is not patterned using electroplating;
Removing the photoresist after forming the metal plating layer;
Coating the photosensitive film on the substrate and the metal plating layer after removing the photoresist;
Applying a tape onto the photosensitive film; And
And removing the substrate.
A method for manufacturing a needle for a probe card.
The method according to claim 1,
Characterized in that the surface-treated metal substrate is a metal substrate with reduced wettability.
A method for manufacturing a needle for a probe card.
3. The method of claim 2,
Characterized in that the wetting angle of the metal substrate with reduced wettability is from 70 to 80 degrees and the surface roughness is from 200 to 300 nm.
A method for manufacturing a needle for a probe card.
The method according to claim 1,
Wherein the step of removing the photoresist comprises using acetone and IPA (isopropyl alcohol)
A method for manufacturing a needle for a probe card.
The method according to claim 1,
Removing the substrate, removing the photosensitive film using acetone, and separating the metal plating layer from the tape to obtain a probe card needles.
A method for manufacturing a needle for a probe card.
A needle for a probe card, manufactured according to the method of any one of claims 1 to 5.

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