KR20110022185A - Micro contact vertical probe - Google Patents

Abstract

PURPOSE: A minute contact probe is provided to improve the electrical contact reliability between a probe and a semiconductor chip pad by projecting the tip to the lower end of the probe. CONSTITUTION: A connection part(101) is fixed to a substrate for the probe card. A tip(103) contacts a contact terminal of the target object perpendicularly. A buffer unit(102) having the elastic force in the vertical direction connects the connection part and the tip. The buffer unit comprises a body(102a) connecting the connection part and the tip and a unit structure(102b).

Description

Vertical Micro Contact Probes {MICRO CONTACT VERTICAL PROBE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe used in a probe card for testing an electronic device. In particular, the present invention relates to a vertical micro contact probe capable of realizing a stable contact while preventing contact damage between a probe card and a semiconductor chip pad. It is about.

Probe cards for testing electronic devices, such as semiconductor devices, are the core components of semiconductor inspection equipment used to test the functionality and performance of semiconductor devices after cutting them, at the wafer level, and before cutting. The types of probe cards that perform inspection at the wafer level after semiconductor processing have various types and sizes used for microprocessors, memory, and flat panel displays (FPDs) .As the chip design has become smaller in recent years, considerable progress has been made in process technology. There is, however, a relatively poor technique for testing equipment to support this. Intel's next-generation chips and flip-chip packaging are currently being developed, but the equipment technology to test them is in trouble.

As is known, a semiconductor device includes a plurality of pads formed on an upper surface thereof for mutual signal communication with an external electronic device. That is, the semiconductor device receives an electrical signal from the external electronic device through the pads, performs a predetermined operation, and then transfers the processed result back to the external electronic device through the pads. In this case, the probes used in the probe card are arranged on a printed circuit board (PCB) of the probe card to be in physical contact with the pad to form an electrical path for signal transmission with an external electronic device.

In recent years, as semiconductor devices have been highly integrated, the spacing and size of pads have also decreased. Since the probes are in physical contact with the pads, this change in pad structure introduces technical difficulties associated with the structure and placement of the probes. One of these technical difficulties is to arrange the probes with a minimum separation distance so as to prevent electrical interference and short between adjacent probes. In addition, in order to reduce the contact resistance between the pad and the probes, the probes need to be overdriven in contact with a predetermined pressure.

However, the contact pressure in the above-described overdrive scheme is obtained in the deformation of the probe and thus the restoring force. Because of this, repeated overdrive contacts can result in morphological deformation of the probes. Such deformation of the probe may result in a decrease in the restoring force of the probe and a deformation of the arrangement position of the probes, thereby lowering the test reliability, and in order to reduce this problem, the probes need to have a sufficiently large restoring force.

In order to improve the restoring force of the probe, a cantilever-type probe card has been conventionally proposed as shown in FIG. 1. The cantilever probe card 10 attaches one side of the support beam 13 to the bumps 12 arranged on the substrate 11. In addition, a tip 14 contacting the pad is attached to the other end of the support beam 13. The tip 14 is press-connected to the pad. In the press-connect, the support beam 13 must have a restoring force by elasticity, and a sufficient length must be ensured in order for the support beam 13 to have a restoring force. If the length of the support beam 13 is too short, it may not have sufficient elasticity, thereby causing a problem of not having sufficient restoring force.

Therefore, the cantilever-type probe card must secure a sufficient length of the support beam, and for this purpose, a sufficient separation distance is necessary between bumps to which the support beam is attached. However, in order to maintain the restoring force of the support beam, a cantilever probe card having a length of the support beam has difficulty in minimizing the distance between the probes. Moreover, as the integration of semiconductor devices has been accelerated in recent years, the gap between probes of probe cards for inspecting highly integrated semiconductor devices has to be further minimized, so the use of cantilever probe cards is more limited.

In addition, since the cantilever probe card is manufactured by attaching a tip to the support beam, it is difficult not only to maintain the overall level at the required level but also to maintain the length of each probe uniformly. In addition, as the degree of integration of semiconductor devices increases, the arrangement of pads is changing from a conventional one-dimensional arrangement (eg, a line) to a two-dimensional arrangement (eg, a matrix). However, the cantilever-type probe card is difficult to be used in the two-dimensional pad arrangement due to technical difficulties such as a large occupation area and a large separation distance of each support beam. In addition, in the cantilever probe card, the support beam may not have sufficient restoring force during the pressure connection, and scratches may occur on the pad on the semiconductor chip as shown in FIG. 2.

Accordingly, the present invention is proposed to solve the above problems according to the prior art.

Firstly, an object of the present invention is to provide a probe having a small occupied area to cope with an increase in the degree of integration of a semiconductor device.

It is another object of the present invention to provide a probe with sufficiently large restoring force.

Another object of the present invention is to provide a probe capable of preventing contact damage of a semiconductor chip pad or a ball of a printed circuit board.

Another object of the present invention is to provide a probe capable of preventing a stress concentration phenomenon of the probe.

According to an aspect of the present invention, there is provided a connecting portion fixed to a substrate for a probe card positioned at an upper end, a tip positioned at a lower end and vertically contacting a contact terminal of an object to be tested, and the connecting portion A plurality of unit structures that connect the tip and have a cushioning portion having a vertical elastic force, wherein the buffering portion has a body connecting the connecting portion and the tip and a 'H' shaped cross section around the body. It provides a probe having.

In addition, the plurality of unit structures may be spaced apart at regular intervals in series along the longitudinal direction of the body.

In addition, the body and the structure may be integrally forming a single structure.

In addition, the upper end of the body connected to the connection portion may be formed to have a 'M' shape.

In addition, the buffer portion may perform vertical behavior during compression.

In addition, the tip may protrude in a direction of a contact terminal of the test object from the central portion of the unit structure.

In addition, the contact terminal of the test object may be an electrode pad or a printed circuit board ball of a semiconductor chip.

As described above, according to the present invention, a micro tip disposed at a lower end of the probe and in contact with a test object, for example, a pad of a semiconductor chip or a ball of a printed circuit board, and a plurality of symmetrical shapes having a vertical elastic force, that is, a body By providing a probe having a buffer having a spring structure in the form of connecting the unit structure having the 'H' shape in series with the center, by providing a contact with the contact terminal of the test object in the vertical direction cantilever according to the prior art It is possible to reduce contact damage to each other than the type probe, and also to effectively cope with the inspection of semiconductor chip pads that are becoming highly integrated.

In addition, according to the present invention, by forming the probe in a vertical structure, it is possible to reduce the occupied area compared to the cantilever type probe according to the prior art and cope with high integration of the semiconductor device.

In addition, according to the present invention, by protruding the tip to the lower end of the probe, it is possible to remove the natural oxide film formed on the inspection object, for example, the upper portion of the semiconductor chip pad during the test inspection, thereby improving the electrical connection reliability between the probe and the semiconductor chip pad. Can be improved.

In addition, according to the present invention, by manufacturing to prevent the vertical load is concentrated through the deformation of the buffer portion during the vertical compression, the vertical load is uniformly applied to the entire probe, causing even deformation without stress concentration on the vertical load, tip Prevents contact damage by preventing the load from concentrating and can flexibly cope with the step of the inspection object.

DETAILED DESCRIPTION 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 technical idea of the present invention. In addition, the parts denoted by the same reference numerals (or reference numerals) throughout the specification represent the same elements.

Example

3 is a view illustrating a probe according to an embodiment of the present invention, Figure 4 is a view showing a state in which the probe shown in Figure 3 is deformed with respect to the load.

3 and 4, the probe 100 according to an embodiment of the present invention is disposed at an upper end and fixed to a connection part 101 fixed to a probe card substrate (not shown), and disposed at a lower end of the probe 100. A tip 103 which vertically contacts a contact terminal (not shown) of the object, and a connecting portion 101 and the tip 103 are connected to each other, and a buffer portion 102 having an elastic force in a vertical direction.

The buffer unit 102 includes a body 102a connecting the connection unit 101 and the tip 103, and a plurality of unit structures 102b having an H-shaped cross section about the body 102a. do.

Body 102a and unit structure 102b are integrally forming a unitary structure. The body 102a has an 'M' shape at its upper end and is connected to the connection portion 101. In addition, the body 102a has a columnar shape perpendicularly connected to the substrate for the probe card through the connecting portion 101.

The unit structure 102b has an overall 'H' shape, and a plurality of unit structures 102b are formed to be spaced apart at regular intervals to surround the body 102a. The unit structure 102b is formed in series along the longitudinal direction of the body 102a in a symmetrical structure with respect to the body 102a.

The tip 103 is disposed at the lower end of the probe 100 and protrudes from the center of the unit structure 102b to remove the contact terminal of the test object, that is, the natural oxide film formed on the semiconductor chip pad. That is, in the overall shape of the probe 100, the tip 103 protrudes from the center of the unit structure 102b formed at the lowermost end (in the direction of the test object) of the body 102a.

As described above, the technical idea of the present invention is merely illustrative, and various changes and modifications can be made by those skilled in the art without departing from the essential characteristics of the present invention. . Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

1 shows a cantilevered probe card according to the prior art.

2 is a view showing that a scratch phenomenon occurs in the electrode pad of the test object in the prior art.

3 illustrates a probe according to an embodiment of the invention.

4 is a view showing a state in which the probe shown in FIG. 3 is deformed with respect to a load;

<Explanation of symbols for the main parts of the drawings>

100: probe

101: connection

102: buffer unit

102a: body

102b: unit structure

103: Tips

Claims (7)

A connection part disposed at an upper end and fixed to a substrate for a probe card; A tip disposed at the lower end and vertically contacting the contact terminal of the test object; And Connecting the connection part and the tip, and having a buffer part having a vertical elastic force, The buffer part, A body connecting the connection part and the tip; And A plurality of unit structure having a cross section of the 'H' shape around the body Probe with. The method of claim 1, The plurality of unit structures, Probes formed spaced apart at regular intervals in series along the longitudinal direction of the body. The method of claim 1, And the body and the structure integrally form a unitary structure. The method of claim 1, The upper end of the body which is connected to the connection portion has a 'M' shaped probe. The method of claim 1, The buffer portion has a vertical behavior during compression. The method of claim 1, The tip protrudes in the direction of the contact terminal of the test object from the center of the unit structure. The method of claim 1, The probe terminal of the test object is an electrode pad or a printed circuit board ball of a semiconductor chip.

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