JPH0737943A - Probe device - Google Patents

Abstract

PURPOSE:To provide a prober, in which a conductive protrusion used as a contact in a probe card is adequately put in contact with an electrode pad in a chip. CONSTITUTION:A movable plate 4 facing to a wafer stage 2 and a link arm 43 are provided so that the movable plate 4 kept in parallel with the wafer (W) can be rotated around an axis in parallel with the wafer (W). A flexible multilayer interconnection board 31 having bumps (conductive protrusions) 32 put in a row is mounted on the rear face of the movable plate 4. Both ends of the wiring board 31 is fixed to a printed board on the upper side. In this constitution, the wiring board 31 is pushed downward by a buffer body 44 in a notch part 41 that passes through the movable plate 4. when the wafer (W) abuts on the bump 32 and moves upward, the bump 32 pushes the electrode pad and slides sideways through rotating force of the movable plate 4 as well as restoring force of the buffer body 44. Then, the bump 32 abrades a natural oxide film on a surface of the electrode pad.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a probe device.

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process,
After the wafer process is completed and an IC chip is completed in the wafer, an electrical measurement called a probe test is performed in order to check the short-circuit and open of the electrode pattern, the input / output characteristics of the IC chip, and the like. The quality of the IC chip is determined in the state of "wafer". After that, the wafer is divided into IC chips, and good ICs
After the chip is packaged, for example, a predetermined probe test is performed to determine the quality of the final product.

In this probe device, as shown in FIG. 4, conventionally, an electrode made of, for example, aluminum of an IC chip in the wafer W is provided above the wafer mounting table 1 which is movable in, for example, the X, Y, Z, and θ directions. Probe needles 11 which are arranged corresponding to the pad arrangement and extend diagonally downward and are called lateral needles 11.
The wafer mounting table 1 is provided with a probe card 12 provided with
Is moved to align the electrode pad of the IC chip in the wafer W with the probe needle 11, and then the probe needle 11 and the electrode pad are brought into contact with each other, and the wafer mounting table 1 is raised by a predetermined amount to perform overdrive. As a result, the natural oxide film of aluminum formed on the surface of the electrode pad is pierced by the probe needle to ensure reliable electrical contact.
Then, the electrode head is connected to the test head 1 through the probe needle 11 and the contact ring 14 including the pogo pin 13 and the like.
5 is electrically contacted, and the quality of the IC chip is determined by performing electrical measurement using, for example, a high frequency corresponding to the operating speed of the IC.

By the way, as the chips become finer and the degree of circuit integration becomes higher, the size of the electrode pads becomes finer and the intervals between them become narrower, and it becomes difficult and difficult to set the needles of the probe needles. For this reason, recently, it has been considered to use a bump made of metal such as 18 gold or nickel as a contact instead of the probe needle.

[0005]

On the other hand, since the surface of the wafer is exposed to the atmosphere, a natural oxide film is formed on the surface. However, in order to obtain reliable contact between the electrode pad and the contact, It is necessary to break through this native oxide and contact the metal surface of the pad. Therefore, in the case of a horizontal needle, which is a conventional probe needle, when the probe needle and the electrode pad come into contact with each other and overdrive is applied, the probe needle bends inward and laterally shifts, thereby scraping the natural oxide film. Breaking through.

However, when the bump is used as the contactor, it does not bend like a horizontal needle even when overdriving, and it is difficult to sharply form the tip of the bump, so that it breaks through the natural oxide film. There is a problem that it is difficult to make sure contact with the surface of the electrode pad.

The present invention has been made under these circumstances, and an object thereof is to ensure that the conductive protrusions on the probe card side and the electrode pads of the device under test are brought into electrical contact with each other with high accuracy. An object of the present invention is to provide a probe device capable of performing high electrical measurement.

[0008]

According to a first aspect of the present invention, a contactor of a probe card is brought into contact with an electrode pad of an object to be inspected placed on an object to be inspected table, and the tester is contacted via the contactor. In the probe device for electrically measuring the object to be inspected by the above, the contactor is constituted by a conductive protrusion, and a moving mechanism for relatively moving the conductive protrusion along the surface to be inspected is provided. The invention according to claim 2, wherein after the sexual projections contact the electrode pads, they are relatively pressed along the surface to be inspected by the moving mechanism in a state where they are pressed against each other. In the probe device in which the contactor of the probe card is brought into contact with the electrode pad of the mounted object to be inspected, and the object to be inspected is electrically measured by the tester through the contactor, the probe card is
A conductive mechanism that forms a contact is arranged on one surface side of a flexible substrate, and a drive mechanism for relatively bringing the probe card and the object mounting base relatively close to each other and the probe card are provided. , For pressing the other surface side of the probe card, and a link mechanism for rotating the surface on which the conductive projections are arranged parallel to the surface to be inspected of the object to be inspected, around a shaft parallel to the surface to be inspected After the electrode pad of the DUT comes into contact with the conductive protrusion, the conductive protrusion is relatively pressed against the restoring force of the buffer means and the probe is provided by the link action of the link mechanism. The feature is that the card is moved along the surface to be inspected.

[0009]

[Function] The object mounting base is brought relatively close to the probe card to bring the conductive projection into contact with the electrode pad,
Next, the conductive protrusion is moved relative to the inspected surface of the inspected object while being pressed against the electrode pad. If the link mechanism according to the second aspect of the present invention is provided, this operation is an operation in which the inspected body and the conductive protrusions are laterally displaced while being pressed against each other after they come into contact with each other. As a result, the conductive protrusions rub the surface of the electrode pad, so that the natural oxide film formed on the surface of the electrode pad is rubbed to surely contact the electrode pad.

[0010]

1 and 2 are a side view showing an embodiment of the present invention and an exploded perspective view showing a main portion thereof, respectively. In the figure, 2 is a wafer mounting table, and the wafer mounting table 2 is a drive mechanism 21.
For example, a slight amount is driven in the X, Y, and θ directions for alignment, and is also driven in the Z direction between the inspection region and the transfer region. This wafer mounting table 2
Includes a lifting pin (not shown) for floating the wafer W from the mounting surface during delivery of the wafer W, and a temperature adjusting unit when performing a high temperature / low temperature test.

A probe card 3 is arranged above the wafer mounting table 2 so as to face the wafer mounting table 2. This probe card 3 is a flexible multilayer wiring board 3
1. For example, an insulating film made of polyimide and a wiring pattern made of copper
And a conductive protrusion arranged on the lower surface side of the substrate 31 so as to collectively contact the electrode pads of all the chips of the wafer W, respectively. A bump 32 made of, for example, 18 gold, platinum, rhodium, tungsten or nickel alloy
And the bumps 32 are, for example, as shown in FIG.
As shown in (b), it is formed in an inverted conical shape that faces downward. The shape of the bump 32 is not limited to this example, and may be a bump shape or the like.

A movable plate 4 is arranged above the probe card 3, and the movable plate 4 is
A rectangular notch 41 having a size enclosing the array region of the bumps 32 is provided at the center, and the left and right sides of the notch 41 have lengths corresponding to the front and rear widths of the substrate 41, respectively. Holes 42, 42 are formed. Further, a printed circuit board 5 having a reinforcing plate 33 stacked on the lower surface side is fixedly provided to the exterior part 50 of the apparatus main body above the movable plate 4, and the printed circuit board 5 and the reinforcing plate 33 are provided. At a position slightly outside the slots 42, 42 in the right and left of the slots 42, 42.
1, 51) and (34, 34) are formed.

The probe card 3 has bumps 3
The area in which 2 are arranged is the cutout portion 41 of the movable plate 4.
Is fixed to the lower surface side of the movable plate 4 so as to face the movable plate 4, and the left and right end portions of the flexible substrate 31 pass through the elongated holes 42 of the movable plate 4, respectively, and further the printed circuit board 5
And the elongated holes (51, 51), (34,
34) and is folded back to the outside to be fixed to the surface of the printed circuit board 5.

The multilayer wiring board 31 has bumps 32, respectively.
A large number of wiring layers that are electrically conductive paths electrically connected to each other are laminated, and a ground potential ground layer is formed between the upper and lower surfaces of the multilayer wiring layer and between the wiring layers. A contact (not shown) on the outer end side is connected to the contact 52 of the printed circuit board 5. On the upper side of the printed circuit board 5, a so-called pogo pin 61 composed of a stretchable conductive pin is vertically arranged, and a contact ring 62 which is an intermediate connector is arranged. The lower end of the pogo pin 61 is a printed circuit board. While contacting the electrode 53 electrically connected to the contact point 52 of 5 through the printed wiring,
The upper end of the pogo pin 61 contacts an electrode (not shown) of the upper test head 63, and thus the test head 63 is electrically connected to the bump 31 which is a contactor via the pogo pin 61 printed board 5 and the multilayer wiring board 31. ing.

A link mechanism having a link arm 43 is provided between the mounting portions 54, 54 provided on the back surface side of the reinforcing plate 33 and the left and right ends of the movable plate 4, and the link arm 43 is provided. Both ends are respectively attached to the mounting portion 54 and the mounting portion 54, so that the movable plate 4 can be moved along an arcuate axis trace that is drawn around the axis parallel to the surface of the wafer W and bulges toward the wafer mounting table 2 side while keeping the movable plate 4 horizontal. It is pivotally supported by the movable plate 4.

The link arm 43 is rotated clockwise in FIG. 1 by a stopper (not shown) so that the link arm 43 is in an oblique state as shown in FIG. 1 when the probe card 3 is not in contact with the wafer W, for example. It has been blocked. On the upper surface of the area where the bumps 32 are arranged in the probe card 3, buffer means for pressing the bumps 32 toward the wafer W via the flexible multilayer wiring board 31, for example, the probe card 3 and the printed circuit board 5. A cushioning member 44 such as an air bag or a rubber mat, which is press-fitted, is provided between and.

Next, the operation of the above embodiment will be described. First, an object to be inspected, for example, a wafer W is transferred from a transfer arm (not shown).
Are transferred to the wafer mounting table 2 via lifting pins (not shown) built in the wafer mounting table 2. Then, the probe card 3 and the wafer W are aligned in the plane direction. This alignment is performed, for example, between the probe card 3 and the wafer W, and between the surface of the wafer W and the bump 32 of the probe card 3.
This can be performed by inserting an optical system unit capable of simultaneously capturing an image of the surface on which the wafers are arranged and adjusting the position of the wafer mounting table 2 in the X, Y, and θ directions while observing both images. However, the alignment may be performed by a method other than this method.

Subsequently, when the wafer mounting table 2 is raised, the electrode pads of all the chips of the wafer W collectively come into contact with all the bumps 32, but when the wafer mounting table 2 is further raised, the buffer 44 is pressed. , Due to the restoring force, the bumps 32 are formed on the wafer W through the flexible multilayer wiring substrate 31.
While pressing the upper electrode pad, the movable plate 4 moves laterally while rising by the link mechanism 43, so that the bumps 32 shift laterally while rubbing the electrode pad. Thus, as described above, the electrode pads on the wafer W are the bumps 32.
Is electrically connected to the test head 63 through this, and in this state, the test head 63 applies a predetermined power supply voltage and a test pulse signal to the chip of the wafer W, and takes in the output pulse signal from the chip side to judge the quality of the chip. .

According to such an embodiment, since the bump 31 comes into contact with the electrode pad and laterally shifts while pressing the electrode pad, the natural oxide film formed on the surface of the electrode pad is rubbed and pierced, so that the electrode pad is surely removed. The metal surface of the electrode pad (for example, the surface of aluminum) can be brought into contact with the electrode pad, and thus good electrical contact can be ensured, so that highly accurate measurement can be performed.

In the above, the probe card 3 is mounted on the wafer W.
As a mechanism for moving in a horizontal direction while pressing, a hard plate is arranged on the back side of the bumps 32 of the multilayer wiring board 31, and a drive mechanism in which a link arm 43 is separately provided after the wafer W and the bumps 32 come into contact with each other. Alternatively, the link mechanism may be provided on the wafer mounting table 2 side. Further, without providing the link mechanism, a mechanism for moving the wafer mounting table 2 and the probe card 3 relatively laterally is separately provided, or the drive mechanism 21 of the wafer mounting table 2 is used, and the wafer W and the bump 32 are provided.
After pressing and, these are relatively laterally displaced, for example X, Y,
Alternatively, it may be moved in the θ direction.

Furthermore, the probe card 3 has bumps 32.
Is not limited to a type in which all of the electrode pads on the wafer W are collectively contacted, but may be a so-called partial multi-type in which some electrode pads are contacted. In this case, bumps The wafer mounting table may be moved so that the 32 groups sequentially contact the electrode pad group. The present invention is not limited to the one in which the wafer mounting table is arranged horizontally, but can be applied to a probe device arranged vertically.

[0022]

According to the first aspect of the present invention, since the conductive protrusions, which are the contactors of the probe card, contact the electrode pads and then move along the surface to be inspected while they are pressed against each other, The conductive protrusion pierces the natural oxide film on the surface of the electrode pad and surely contacts the electrode pad, which allows highly accurate measurement.

According to the second aspect of the present invention, the probe card is moved along the surface to be inspected by the link mechanism while moving toward the side opposite to the surface to be inspected, while the buffer means presses it toward the object to be inspected. The conductive protrusion can be laterally displaced with respect to the electrode pad without any difficulty, and therefore, the abrasion of the conductive protrusion can be suppressed.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a main part of the embodiment of the present invention.

FIG. 3 is a side view showing bumps (conductive protrusions).

FIG. 4 is a vertical cross-sectional view showing a conventional probe device.

[Explanation of symbols]

 2 Wafer mounting table 3 Probe card 31 Multi-layer wiring board 32 Bump 4 Movable plate 43 Link arm 44 Buffer 5 Printed board 62 Contact ring 63 Test head 63 Semiconductor wafer

Claims (2)

[Claims] 1. A probe in which a contact of a probe card is brought into contact with an electrode pad of an object to be inspected mounted on an object to be inspected table, and a tester electrically measures the object to be inspected through the contact. In the device, the contactor is constituted by a conductive protrusion, and a moving mechanism for relatively moving the conductive protrusion along a surface to be inspected is provided, and after the conductive protrusion comes into contact with the electrode pad, these are arranged. A probe device, wherein the probe device is relatively moved along the surface to be inspected by the moving mechanism while being pressed against each other. 2. A probe in which a contact of a probe card is brought into contact with an electrode pad of an object to be inspected placed on an object to be inspected table, and a tester electrically measures the object to be inspected through the contact. In the apparatus, a probe card is configured by arranging conductive protrusions forming contacts on one surface side of a flexible substrate, and driving for relatively bringing the probe card and the object mounting base relatively close to each other. And a link mechanism for rotating the probe card around an axis parallel to the surface to be inspected while the surface on which the conductive protrusions are arranged is parallel to the surface to be inspected of the object to be inspected. A buffer means for pressing the other surface side, and after the electrode pad of the device under test contacts the conductive protrusion, the conductive protrusion is relatively pressed against the restoring force of the buffer means, and Plow by the link action of the link mechanism A probe device for moving a bucard along the surface to be inspected.