JPH07111991B2 - Wafer prober - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a wafer prober for performing a characteristic test of a semiconductor wafer.

(Prior Art) As is well known, semiconductor wafer chips (hereinafter referred to as chips)
Are simultaneously formed on a semiconductor wafer (hereinafter referred to as a wafer). Generally, the wafer has a broken crystal part, and a chip including this defective part is a defective product. Therefore, the wafer after the chip forming process is normally subjected to an automatic tester called a wafer prober, a test is performed as to whether the circuits in each chip are normally operated, and a defective chip is marked. . The above test is performed by connecting the tester and the wafer prober. The schematic structure of the wafer prober includes a mounting table for holding the wafer horizontally, an XY driving device for moving the mounting table in the XY direction in a horizontal plane, and a lifting table for freely moving the mounting table. The elevating device and the θ-rotating device rotatable in the circumferential direction are provided, and the mounting table is mounted on the base of the wafer prober via rails. Explaining with reference to FIG. 2, a main pillar (8) is erected from the base, and a head plate (9) is erected so as to cover the mounting table (6) based on the main pillar (8). . A connecting portion such as the intermediate substrate (20d) is located so as to be internally provided in the head plate (9). On the other hand, the schematic structure of the tester is that the support (1a) is screwed onto the high frequency test head (1k), and the groove (1e) of the support is attached.
Structure or substrate (hereinafter,
This is a structure in which a structure / substrate (1c) is installed so that it can swing horizontally.

The connection part (1s) between the wafer prober and the tester will be described. The ring insert (20b) of the connection part on the wafer prober side is provided in the head plate (9) and is rotatable about the circumference. The insert (20b) is provided with a structure such as a double-sided pogo pin or a connection mechanism (hereinafter referred to as a connection mechanism) (20c) such as a socket, and
The intermediate board (20d) is attached to the ring insert (20b) and screwed together. In this way, the probe (40
b) makes contact, and the signal is conducted from the probe card (40) to the pressure contact surfaces (51, 50, 52) of the connection mechanism and is input / output to / from the test head. Note that 1b is measuring, 1d is a connecting mechanism, 1g is a positioning hole, and 20c is a housing.

(Problems to be Solved by the Invention) However, the connection portion between the tester and the wafer prober described above has the following drawbacks.

Since the ring insert is interposed in the space between the connection part of the tester and the wafer on the mounting table, the connection part of the tester is in contact with the probe card (40) by the interposition of the intermediate substrate (20d). . That is, since the ring insert is interposed in the space between the tester and the wafer, the space between the tester and the wafer cannot be narrowed. Therefore, although the length of the measuring cable is required to be several cm or less, there is a drawback that the request cannot be met and only a test result with low reliability can be obtained.

An object of the present invention is to provide a wafer prober aiming to eliminate the above-mentioned drawbacks and realize highly reliable electric characteristics.

(Means for Solving Problems) The semiconductor wafer to be tested is mounted on a mounting table that can be driven in the X, Y, Z directions and the circumferential direction, and an electric signal is output to the chip of the semiconductor wafer to output from the chip. A test head for processing the electric signal of the semiconductor wafer is arranged to face the semiconductor wafer, and the probe tip of the replaceable probe card and the electrode of the chip on the semiconductor wafer, which are arranged to face the semiconductor wafer, are driven. In a wafer prober that performs an electrical test on a semiconductor wafer by positioning and contacting the probe card with the test head, the probe card is rotated in the circumferential direction to adjust the angle of the probe probe in the circumferential direction. Adjusting means, and a socket which is held by the test head via the adjusting means and which transmits an electric signal of the test head. A substrate and provided, wafer prober, characterized in that freely is held removably the probe card with respect to the substrate by inserting a pin provided on a probe card in the socket.

(Operation) A wafer is placed on the mounting table and, for example, the mounting table is set to X, Y, θ.
Drive the wafer to pre-align the wafer. Next, move the mounting table to the lower side of the probe card, raise the wafer so that it is located near the probe probe of the probe card, and bring the probe probe into contact with the predetermined area of the electrode pad of the chip of the wafer. Then, the angle of the probe card in the circumferential direction is adjusted by the adjusting means. After the adjustment, the probe tip and the electrode pad are brought into contact with each other, an electric signal is output from the test head to the chip, and the electric signal from the chip is processed to electrically measure the chip. Such a measurement is performed sequentially for each chip by driving the mounting table,
The quality is judged and automatically recorded in the memory map.

Since the probe card is held by the test head via the adjusting mechanism and the substrate, the signal path between the probe probe and the test head is short, and accurate measurement can be performed. Further, since the probe card is detachably attached to the substrate, it is easy to replace the probe card.

Embodiment An embodiment of the present invention will be described below with reference to FIG.

Reference numeral (60) is an entire tester for judging a wafer chip, and the bottom surface 1j of the test head (60b) of the tester (60) covered with the wafer prober is adjustable in the XY direction and the circumferential direction. Adjusting means (60c) is attached and the adjusting means (60c)
A substrate (60d) is erected and carried on c).

Reference numeral (67) is a probe card having a probe probe 60e that comes into contact with the electrode pad of the chip. The board 60d is provided with a socket 71 for transmitting an electric signal of the test head 60b to the probe card 67, while the probe card 67 is provided.
Is provided with an insertion pin 72, and by inserting the insertion pin 72 into the socket 71, the probe card 67 becomes a board 60d.
It is detachably attached to.

Reference numeral (5) is a wafer that is adsorbed and held on the mounting table (61).

Reference numeral (61a) is a peripheral rotation device for rotating the wafer (5) sucked and held on the mounting table (61) in the peripheral rotation direction to rotate the scribe line of the wafer in the peripheral direction.

Reference numeral (61b) indicates that the wafer (5) transferred from the wafer cassette (not shown) is attracted to the mounting table (61), and then the wafer (5) contacts the probe probe (61e) of the probe card (67). It is an elevating device for raising and lowering the mounting table (61).

Reference numeral (61c) is an XY drive device that drives the mounting table that has attracted the wafer in the XY directions.

Reference numeral (63) is a rotating device that covers the wafer prober main body (62) with the tester (60) via the arm 64.

After the test head (60b) is covered on the wafer prober body (62) by the rotating device (63), the wafer (5) transferred from the wafer cassette (not shown) is placed on the mounting table (61). Adsorb and place the mounting table (61) in the horizontal plane,
XY drive device (61c) for moving in XY direction
Then, the wafer is moved to the wafer alignment device (80) and the scribe run of the wafer (5) is aligned in the XY directions. This alignment device (80) is called alignment, which is a known technique performed by a conventional wafer prober. After aligning the scribe line of the wafer (5) with the aligning device (80), the XY driving device (61c) again moves the scribe line to directly below the test head (60b), and the lifting device (61b) is used. As the stand (61) is raised and the probe probe (60e) is approached, the raising speed is reduced. And a visual device such as a microscope or a TV camera that is installed above the test head (60b).
At 65, confirm the engagement between the electrode pad of the chip and the probe probe (60e). As a result of the confirmation, when the probe tip (60e) is displaced and engaged with the electrode pad of the chip,
The deviation in the XY direction and the deviation in the circumferential direction of the adjusting means (60c) are properly corrected. Further, the probe probe (60e) comes into contact with the wafer (5), and the deflection amount of the probe probe (60e) is raised by raising it on the mounting table (61). All the chips in the wafer (5) are tested while stepping from chip to chip by repeating the above steps.

EFFECTS OF THE INVENTION According to the present invention, the probe card that is held on the wafer prober main body side and is rotated around is configured to be held and rotated on the test head side. The connection mechanism connecting the test head and the test head can be simplified. First, the distance of the electrical connection between the two can be shortened, and first, the number of contacts by, for example, the contact pin and the electrode on the substrate can be reduced. Since the resistance of the electric signal can be reduced and the electric signal is less likely to be attenuated, highly accurate measurement can be performed when a high-speed test is performed using a high frequency.

Since the probe card is detachably attached to the rotatable substrate by the adjusting means, adjustment is required when converting the probe card, for example, when converting to another type of probe card depending on the type of chip. It is not necessary to provide each probe card with a portion that cooperates with the means, for example, flanges arranged at intervals in the circumferential direction, so that the structure of each probe card does not become complicated and the probe card can be easily attached and detached. It can be carried out.

Further, since the probe card can be rotated in the circumferential direction, it is convenient, for example, to adjust the probe needle so as to be within the visual field of the visual device when the probe card is attached.

[Brief description of drawings]

FIG. 1 is a side view and a sectional view showing the overall structure of a wafer prober of the present invention. FIG. 2 is a side sectional view of a conventional wafer prober. 1a …… Post 1b …… Measuring 1c …… Structure or substrate that holds the connection 1d …… Connection mechanism 1e …… Post groove 1g …… Alignment hole 1j …… Test head bottom 1s …… Connection 8 …… Main pillar 9 …… Head plate 20b …… Ring insert 20c …… Housing with pogo pins on both sides 20d …… Intermediate board 20e …… Connecting mechanism 40b …… Probe 50 …… Pressure contact surface 51 …… Pressure contact surface 52 …… Pressure contact surface 65 …… Visual device

Claims (2)

[Claims] 1. A semiconductor wafer to be tested is mounted on a mounting table which can be driven in X, Y, Z directions and a circumferential direction, and an electric signal is output to a chip of the semiconductor wafer to output an electric signal from the chip. A test head to be processed is arranged facing the semiconductor wafer, and a probe tip of a replaceable probe card and a chip electrode on the semiconductor wafer arranged facing the semiconductor wafer are positioned by driving the mounting table. In a wafer prober that performs an electrical test on the semiconductor wafer by bringing them into contact with each other, an adjusting unit provided in a test head for rotating the probe card in the circumferential direction to adjust the circumferential angle of the probe probe. A substrate provided with a socket which is held by the test head through the adjusting means and which transmits an electric signal of the test head; Provided, wafer prober, characterized in that freely is held removably the probe card with respect to the substrate by inserting the insertion pin provided on a probe card in the socket. 2. A test head is rotatably provided around an axis parallel to a mounting table on which a semiconductor wafer is mounted by a rotating device provided on a wafer prober, and the test head is arranged to face the semiconductor wafer on the mounting table. The wafer prober according to claim 1, wherein: