KR20080109271A - Method for producing probe card - Google Patents

Abstract

A probe card manufacturing method is provided to reduce the whole process time without performing the formation of the photoresist layer, the etching removal process, and the conductivity metallic plating operation and polishing operation. A probe card manufacturing method comprises the following steps: the step for preparing the substrate(100) having the plurality of upper side terminals which are electrically connected to the plurality of wire portions; the step for preparing the silicon wafer sacrificial substrate and forming the plurality of penetration holes corresponding to the plurality of upper side terminals on the silicon wafer sacrificial substrate; the step for positioning the silicon wafer sacrificial substrate on the substrate corresponding to the plurality of penetration holes formed on a plurality of upper side terminal; the step for forming the plurality of base parts by introducing respective conductive metal through a plurality of penetration holes; the step for combining and fixing the plurality of probes(600) formed on a plurality of base parts.

Description

Method for producing probe card

1 schematically shows a probe card manufactured according to a conventional probe card manufacturing method.

2A to 2C schematically illustrate a substrate preparation step in a method of manufacturing a probe card according to an embodiment of the present invention.

3A to 3C schematically illustrate a step of preparing a sacrificial substrate in a method of manufacturing a probe card according to an embodiment of the present invention.

4A to 4F schematically illustrate a proximal end forming step of a probe in a method of manufacturing a probe card according to an embodiment of the present invention.

5 schematically shows a cross section of a probe card made in accordance with one embodiment of the present invention.

The present invention relates to a method of manufacturing a probe card, and more particularly, to a method of manufacturing a probe card capable of forming a proximal end portion of a probe of a probe card using a silicon wafer as a sacrificial substrate.

A wafer probing apparatus is an apparatus for electrically testing each individual semiconductor chip formed on a wafer by using a probe card, and the probe contacts a metal pad of each individual semiconductor chip so that a test can be performed.

The probe of the probe card for performing the electrical test of each individual semiconductor chip on the wafer is generally used in the form of a needle (also referred to as a 'probe needle'), and each of these probes is mounted on a probe card. However, it is not preferable to mount a needle-shaped probe on a probe card in terms of its manufacturing time and cost.

Therefore, a method of simultaneously manufacturing a plurality of probe card probes by using a semiconductor etching technology has been studied.

Hereinafter, a method of manufacturing a conventional probe card using a semiconductor etching technique will be described in detail with reference to FIG. 1.

First, as shown in FIG. 1, after the photoresist layer is formed of a photoresist material on the substrate 10, the photoresist layer around the wiring part 11 is etched away, and then the wiring part 11 is etched away. ) To form a bump 20 of the probe by plating a metal.

Thereafter, a photoresist layer is further formed, the portions corresponding to the beams of the probes are etched away, and then the metals are plated on the etched portions to form the bodies 30 of the probes. To form a tip portion 40 of the probe.

However, in the conventional method, since the thickness of the photoresist layer formed on the substrate 10 is formed by applying a photoresist material, it is difficult to form a predetermined thickness (80 μm) or more. Therefore, when the height of the base end of the target probe was 300 micrometers or more, the photoresist layer had to be repeated 3 times or more. That is, the photoresist layer formation, the etching removal process, the metal plating process, and the polishing removal process of the protruding metal plating had to be repeated several times or more. Therefore, the process takes a long time, the base end portion 20 is formed in a multi-layer as shown in FIG.

However, in the base end portion 20 formed in this manner, the bonding force between the layers is not good, the process stress is applied in the repeated polishing removal process, so that the yield is low during the manufacturing process, and the contact with the contact portion of the semiconductor element repeated during the probing of the wafer. There is a problem that is easily broken by.

In order to solve the above problems of the prior art, the present invention provides a novel probe card manufacturing method capable of forming a proximal end of a probe having a sufficient height without repeating the formation of the photoresist layer, the etching removal process, and the polishing removal process. To provide.

In addition, the present invention is to provide a novel probe card manufacturing method that can form the base end of the desired height in one metal plating process.

According to an aspect of the present invention, there is provided a method of manufacturing a probe card, the method comprising: preparing a substrate having a plurality of wiring units and a plurality of upper surface terminals electrically connected to one ends of the plurality of wiring units and attached to an upper portion thereof; ; Preparing a silicon wafer sacrificial substrate and forming a plurality of through holes on the silicon wafer sacrificial substrate so as to correspond to positions corresponding to the plurality of top terminals, respectively; Placing the silicon wafer sacrificial substrate on the substrate such that the plurality of through holes formed in the plurality of upper surface terminals correspond to each other; Forming a plurality of proximal ends by introducing conductive metals into the upper portions of the plurality of upper surface terminals, respectively, through the plurality of through holes; And coupling and fixing the plurality of probes formed separately to the plurality of proximal ends.

The plurality of probes may have a locking portion formed of two or more legs on one side thereof. Engaging portions of the plurality of probes may be elastically coupled to the plurality of proximal ends, respectively, in which case, concave portions are formed on both sides of the plurality of proximal ends, so that the engaging portions of the plurality of probes are coupled to the recesses. Can be. In addition, the W-shaped inner space is formed inside the plurality of base ends, the engaging portion of the plurality of probes may be coupled to the inner space.

In the method of manufacturing the probe card, in the preparing of the substrate, after forming a photoresist layer on the substrate, only the portions corresponding to the plurality of top terminals are etched away to remove the plurality of mold portions corresponding to the plurality of base ends. It may further comprise the step of forming.

In the method of manufacturing the probe card, in the step of placing the silicon wafer sacrificial substrate on the substrate, the plurality of mold portions and the plurality of through holes may communicate with each other.

The method of manufacturing the probe card may include preparing the plurality of probes; And fixing the plurality of probes at positions corresponding to the plurality of base ends through the fixing substrate.

The conductive metal cloud may be nickel, nickel cobalt alloy or nickel iron alloy.

In order to achieve the above technical problem, in the present invention, a mold corresponding to the proximal end of the probe is separately formed by using a silicon wafer having a thickness corresponding to the height of the proximal end of the desired probe, and the metal is used once. By performing the plating process to form the proximal end of the probe, the proximal end of the probe can be formed without repeating the formation of the photoresist layer, the etching removal process, and the polishing removal process.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

First, as shown in FIG. 2A, a silicon substrate or a laminated ceramic substrate is prepared as the substrate 100. The substrate 100 is connected to the wiring part and one end of the wiring part therein, and is connected to the upper surface terminal 130 attached to the upper surface of the substrate 100 and the other end of the wiring part and the lower surface terminal attached to the lower surface of the substrate 100. There is no particular limitation as long as it is formed, but is preferably made of a ceramic material and a commercially available space transformer may be used. In the drawings of the present invention, for convenience of description, the wiring part and the bottom terminal are not illustrated, and only one top terminal 130 is illustrated on the substrate 100. However, the number of the top terminal 130 is not limited, and generally, It is formed in plural.

The metal films 110 and 120 are formed in two layers below the prepared substrate 100. The metal films 110 and 120 may be formed by applying a chemical vapor deposition (CVD) method or a sputtering method, but the formation method is not particularly limited. The metal films 110 and 120 are used as electrodes in a plating process for forming a proximal end. In the embodiment of the present invention, the metal film is formed of two layers, but is not limited thereto.

Thereafter, as shown in FIG. 2B, a photoresist material was applied on the substrate 100 and baked at a constant temperature to form a photoresist layer 200.

Here, the photoresist material may be a positive photoresist material that is a material that breaks the bond chain of the polymer in the exposed site when exposed, or a negative photoresist material that the bond chain of the polymer in the exposed site is firm when exposed. . The photoresist layer 200 thus formed generally has a thickness of 80 μm or less.

As such, when the photoresist layer 200 is formed, only a portion corresponding to the upper terminal 130 of the substrate is selectively exposed through a mask (not shown), so that the photo of the exposed portion of the photoresist layer 200 is exposed. The resist material is altered and removed using an etching solution that can selectively etch away the altered portion. As a result, only the portion corresponding to the upper surface terminal 130 in the photoresist layer 200 is etched away to form a mold portion 210 for the proximal end of the probe for the probe card as shown in FIG. 2C. The etching method is not particularly limited, and dry etching may be used in addition to the wet etching method described above.

On the other hand, the shape of the mold portion 210 is not particularly limited, but preferably may be provided in the form having a yaw portion on both sides.

In FIG. 2C, the thickness of the photoresist layer 200 is shown to be thicker than the height of the upper terminal 130, but the thickness of the photoresist layer 200 is not particularly limited as long as the thickness of the photoresist layer 200 is greater than or equal to the height of the upper terminal 130.

Thereafter, the bonding material may be further applied on the photoresist layer 200 except for the mold part 210. This bonding material assists in bonding to the silicon wafer sacrificial substrate in a later process.

Next, after preparing the silicon wafer as a sacrificial substrate, as shown in Figure 3a, the silicon wafer is polished to a thickness corresponding to the height of the proximal end of the probe to be manufactured. This polishing method is not particularly limited and preferably uses chemical mechanical polishing (CMP). In the present invention, the height of the proximal end is not particularly limited, and may be preferably 300 μm or more. As described above, in the present invention, the thickness of the silicon wafer whose thickness exceeds the height of the proximal end of the probe for the probe card is prepared to correspond to the height of the proximal end of the probe. There is no need to repeat the resist formation, the etching removal process, the polishing removal process, and the like.

Thereafter, as shown in FIG. 3B, the portion corresponding to the proximal end of the probe is performed on the silicon wafer thus adjusted by the thickness until the silicon wafer is penetrated by a deep reactive ion etching method. The base end through hole 310 is formed. The shape of the through-hole 310 is not particularly limited, but preferably may be provided in the form having a yaw portion on both sides.

In addition, the oxide layers 410 and 420 are formed by oxidizing both surfaces of the silicon wafer on which the through holes 310 are formed. This oxide film is used as an insulating film in a metal plating process later.

Thereafter, the silicon wafer sacrificial substrate 300 having the through hole 310 corresponding to the proximal end of the probe is aligned with the substrate 100 prepared by FIG. 2. At this time, as shown in Figure 4a, the through hole 310 of the sacrificial substrate 300 is positioned on the mold portion 210 of the substrate 100 to communicate with each other, so that the sacrificial substrate 300 and the substrate 100 Align the position.

Thereafter, the sacrificial substrate 300 and the substrate 100 are pressed to each other and bonded. In this case, a bonding material may be applied between the sacrificial substrate 300 and the substrate 100 to assist the bonding.

Thereafter, as shown in FIG. 4B, the metal parts 110 and 120 are used as electrodes to fill the inside of the mold part 210 and the through hole 310 with a conductive metal according to an electroplating method. Form 500.

After forming the proximal end 500, as shown in FIG. 4C, the conductive metal portion protruding out of the through hole 310 is ground by chemical mechanical polishing (CMP) or the like. At this time, the thickness of the base end 500 can be adjusted again to a predetermined thickness. The shape of the base end 500 is not particularly limited, but preferably may be provided in the form having a yaw portion on both sides.

The base end 500 formed as described above is electrically connected to the upper terminal 130 of the substrate 100 and the wiring unit connected to the upper terminal.

In this case, as the conductive metal used for forming the proximal end, a metal having excellent elasticity and conductivity is used. Preferably, nickel or nickel alloy, specifically nickel cobalt alloy or nickel iron alloy is used. As described above, since the proximal end is made of a metal having excellent elastic force, the proximal end according to an embodiment of the present invention can be coupled with a stronger bonding force when elastically coupled with the engaging portion of the probe to be described later.

Thereafter, as shown in FIG. 4D, after the silicon wafer sacrificial substrate 300 is selectively etched away with an etching solution such as KOH, as shown in FIG. 4E, the oxide film 420 and the photoresist layer 200 are removed. ) Is selectively etched away. At this time, alkali solvents, such as acetone, are used suitably as an etching solvent.

As shown in FIG. 4F, the substrate 100 on which the proximal end 500 of the probe for the probe card is formed is removed by removing the metal films 110 and 120 used as electrodes in the plating process.

On the other hand, the body portion of the probe to be fixed by the proximal end 500 of the probe thus formed is prepared separately. Thus prepared body portion of the probe (hereinafter, also referred to as simply a probe) in the embodiment of the present invention preferably has a planar shape, that is, two-dimensional shape according to a semiconductor process such as MEMS (MEMS). Since the probe manufacturing method may be performed by a conventional semiconductor process, a detailed description thereof will be omitted.

When the probe having the two-dimensional shape is prepared as shown in FIG. 5, the probe 600 is fixed to the proximal end 500. At this time, the proximal end 500 electrically connects the probe and the upper terminal 130 of the substrate 100 to each other. In the present invention, the proximal end 500 is preferably formed at a suitable height according to the shape of the corresponding probe.

The probe 600, which is formed in the two-dimensional MEMS method separately on the base end 500 formed as described above, is fixedly coupled as shown in FIG. 5 to form a probe card.

The probe 600 is formed in a shape having a locking portion composed of two or more legs so as to be firmly coupled to both sides of the proximal end 500 by an elastic force. It is more preferable that an empty space is formed between the two legs of the locking portion. In this shape, the locking portion has an elastic force in the empty space direction. Therefore, when the legs of the probe 600 having the locking portion are coupled to both sides of the base portion 500, the probe 600 may not be easily separated from the base portion 500 of the substrate 100 due to the elastic force of the locking portion. However, the shape of the probe 600 is not limited to that shown in FIG. 5 and may be appropriately modified according to the purpose of the invention.

In the exemplary embodiment of the present invention, the proximal end 500 may be formed in various shapes. For example, the proximal end 500 may be formed on both sides of the proximal end 500 to facilitate coupling with the probe. When recesses are formed on both sides of the base end 500 in this manner, as shown in FIG. 5, both legs of the locking portion of the probe may be firmly coupled to the pair of recesses on both sides of the base end 500. As another example, the proximal end 500 may be formed in a K-shape so as to have a space therein, in which case the probe 600 is inserted into an inner space of the proximal end 600, and the catching portion of the probe 600 is provided. The inner space of the base end 600 is firmly coupled to the elastic force. In FIG. 5, for convenience, one probe 600 is illustrated as being coupled to one proximal end 500, but in the actual probe card, a plurality of probes 600 are coupled to the plurality of proximal end 500, respectively. Will be constructed.

Meanwhile, in order to simultaneously fix the plurality of probes 600 to the substrate 100 on which the plurality of base ends 500 are formed, the probe card of the present invention has a position where the plurality of probes 600 corresponds to the plurality of base ends 500. It is possible to use a separate fixed substrate (not shown) that is inserted and fixed in advance. In this case, the probe card of the present invention is completed by aligning and fixing the fixed substrate on which the plurality of probes 600 are fixed on the substrate 100 on which the plurality of base ends 500 are formed.

Using the method of manufacturing a probe card of the present invention, there is no need to repeat the formation of the photoresist layer, the etching removal process, the conductive metal plating process, and the polishing process to form the proximal end of the probe, thereby reducing the overall process time. The shortened, proximal end of the desired height can be formed in one metal plating process.

On the other hand, by using the method of manufacturing the probe card, it is possible to minimize the formation of the photoresist layer, the etching removal process, the conductive metal plating process, and the polishing process, thereby minimizing the process stress, and thus the process of the probe during the manufacturing process The collapse of the proximal end can be minimized.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications can be made within the scope of the technical idea of the present invention, and it is obvious that the present invention belongs to the appended claims. Do.

Claims (10)

Preparing a substrate having a plurality of wiring units therein and a plurality of upper surface terminals electrically connected to one ends of the plurality of wiring units and attached to an upper portion thereof; Preparing a silicon wafer sacrificial substrate, and forming a plurality of through holes on the silicon wafer sacrificial substrate to respectively correspond to positions corresponding to the plurality of top terminals; Placing the silicon wafer sacrificial substrate on the substrate such that the plurality of through holes formed in the plurality of upper surface terminals correspond to each other; Forming a plurality of proximal ends by introducing conductive metals into the upper portions of the plurality of upper surface terminals, respectively, through the plurality of through holes; And Coupling and fixing a plurality of probes separately formed on the plurality of proximal ends; Probe card manufacturing method comprising a. The method of claim 1, The probe card manufacturing method, characterized in that the height of the proximal end is 300㎛ or more. The method of claim 1, The probe card manufacturing method, characterized in that the engaging portion consisting of two or more legs is provided on one side of the plurality of probes. The method of claim 3, The method of manufacturing the probe card, characterized in that the engaging portions of the plurality of probes are respectively elastically coupled to the plurality of base ends. The method of claim 4, wherein The yaw portion is formed on both sides of the plurality of proximal end portions, and the engaging portion of the plurality of probes is coupled to the recess portion. The method of claim 4, wherein The? Card-shaped inner space is formed inside the plurality of base ends, and the engaging portion of the plurality of probes is coupled to the inner space. The method of claim 1, In the preparing of the substrate, after forming the photoresist layer on the substrate, the step of forming a plurality of mold portions corresponding to the plurality of proximal ends by etching away only the portions corresponding to the plurality of upper surface terminals; The probe card manufacturing method, characterized in that. The method of claim 7, wherein In the positioning of the silicon wafer sacrificial substrate on the substrate, the plurality of mold parts and the plurality of through holes communicate with each other. The method of claim 1, Preparing the plurality of probes; And Fixing the plurality of probes to positions corresponding to the plurality of base ends through a fixing substrate; The probe card manufacturing method characterized in that it further comprises. The method of claim 1 And the conductive metal is nickel, nickel cobalt alloy or nickel iron alloy.

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