JPH01265531A - Probe card - Google Patents

Abstract

PURPOSE:To equalize the life and pressure of probes by a method wherein brades whereto the base ends of probes in the same length as that of the other probes of a probe card are provided on the surface of a printed substrate while the ends of the probes are enabled to be set up at arbitrary positions. CONSTITUTION:Brades 10 whereto the base ends of probes 9 in the same length as that of the other probes 11 of a probe card 6 are fixed are provided on the surface of a printed substrate 7. The electrode pads 14 formed on the peripheral part of a semiconductor wafer are brought into contact with the probes 11 on the rear surface 7b of the substrate 7 while the electrode pads 14 formed on the central position of a semiconductor wafer chip 13 are brought into contact with the probes 9 fixed to the brades 10 provided on the surface of the substrate 7. The deflection level of the probes 9, 11 are equivalent with each other since the lengths of these two kinds of probes 9, 11 are equal. Through these procedures, the life and pressure of these probes 9, 11 are equalized.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a pronib card.

(Prior Art) Conventional probe cards for measuring semiconductor wafers are described in Japanese Patent Publication No. 58-34935, Japanese Utility Model Application Publication No. 60-118964, Japanese Utility Model Application Publication No. 59-43091, and Japanese Utility Model Application Publication No. 59-11443. There is.

In the above-mentioned Japanese Utility Model Publication No. 59-11443, a stepped portion, for example, a ring rubber, is fixed to the back side of the circuit board, and the ring rubber is fixed with an epoxy resin adhesive, and the negative end is connected to the conductor of the board. It is something.

The above-mentioned Japanese Utility Model Publication No. 60-11.8964 is a blade-type probe card in which a plurality of blades each having a proximal end of a stylus substrate fixed to the tip thereof are arranged along the periphery of an opening in the substrate.

(Problems to be Solved by the Invention) However, in the conventional probe cards described above, as the degree of integration of semiconductor wafers has improved, the number of electrode pad positions within the semiconductor wafer chips has increased. For example, DRAM (DRAM) semiconductor wafer chips of 1M or more are now being provided with a new electrode pad (2) approximately at the center of a rectangular shape with a width of 6 rm and a length of 17 mm, as shown in FIG. In the probe card ■, which is formed with a probe insertion point 〇 that contacts this electrode pad ■ and a probe needle B (A) that contacts the electrode pad ■ provided on the periphery of the short side of the semiconductor wafer chip, the probe needle The length of A■ and the above probe needle B (A), for example, ℃□,
Since the probe needles (2, 3) have different lengths such as 2□, the lifespan of each probe needle (2, 3) is different.

Since the lengths of the probe needles (2, 3) are different, the needle pressure and the contact resistance of the tips of the probes against the electrode pad surface are different, making it impossible to perform accurate measurements. In addition, the respective lifespans and height variations of the probe needles (2, 3),
Probe needle (2, 3) marks on the position accuracy electrode pad;
There were problems in that variations occurred in the inductance, insulation resistance, conductor resistance of the probe needle, and the introduction angle of the capacitance probe needle (hereinafter referred to as the stylus).

The object of the present invention has been made in view of the problems of conventional probe cards.Even if the electrode pads of a semiconductor wafer chip are arranged in the center of the semiconductor wafer chip, To provide a probe card capable of contacting electrode pads with the same lifespan and with the same stylus force even if the electrode pads are arranged in the same direction.

[Structure of the invention]

(Means for Solving the Problems) The probe card of the present invention has a plurality of stylus arranged and fixed in a fan shape on the back side of an open printed circuit board. It is characterized in that a blade to which the proximal end of a long stylus is fixed is provided on the surface of the printed circuit board.

(Function) The probe card of the present invention has a blade on the surface of the printed circuit board and a stylus on this blade.
It becomes possible to set the tip of this stylus at any position.

That is, when an electrode pad is formed in the center of a semiconductor wafer chip, the blade is fixed to the surface of the printed circuit board at a position where the tip of the stylus contacts the electrode pad.

Since a stylus of a certain length is arranged on the back surface of the printed circuit board, it is possible to contact the peripheral electrode of the semiconductor wafer chip.

Therefore, the length of the stylus provided on the front surface of the printed circuit board and the stylus provided on the back surface are constant, and the height of the tip of the stylus is the same, so that the stylus formed on the periphery of the semiconductor wafer chip The tip of the stylus provided on the back surface comes into contact with the electrode.

Further, the tip of the stylus provided on the front surface contacts the electrode formed at the center of the semiconductor wafer chip at the same time as the tip of the stylus provided on the back surface contacts the semiconductor wafer chip.

Since the length of the stylus is constant, the amount of deflection of each stylus is the same, so the metal fatigue is also the same. Therefore,
The lifespan will be approximately the same. Also, since the stylus strength is the same, the stylus pressure at the tip of each stylus is the same. Furthermore, since the stylus pressure is the same, the contact resistance is also the same.

(Embodiment) An embodiment of the probe card of the present invention will be described below with reference to the drawings.

First, the probe card (2) will be explained using FIG.

The overall configuration of the probe card 0 is a board with a hole, for example, a rectangular hole (c) larger than the external shape of the semiconductor wafer chip to be measured, in the center of an epoxy flat plate with printed wiring on both sides. A plurality of blades (10) are fixed to the front surface (7a) of this board (2), one end is fixed to the back surface (7b) of this board (2), and the other end is gathered in a fan shape in the rectangular hole (2) of the board. It is composed of a plurality of stylus needles (11) provided as shown in FIG.

The structure of the surface (7a) of the substrate (2) will be explained.

First, the outer shape of the board (2) is, for example, a rectangular outer shape, and a connecting portion (12) to be connected to a tester (not shown) is formed on one side of this outer shape.

Electrical wiring is provided between this connecting portion (12) and the connecting portion of the blade (10) formed at the periphery of the rectangular hole (2). The connection end of this blade (10) to the board is one end (10a) of the blade (10), as shown in FIG.
are electrically connected and fixed. This blade (1
A stylus 0 is provided at the other end (10b) of 0) with a certain length, for example a length of L. When the semiconductor wafer chip (13 in Fig. 2) to be measured is placed, the stylus (■) fixed to the blade (10) with the length L is connected to the electrode pad formed in the center of this semiconductor wafer chip. (14) is provided on the substrate (2) so as to be placed in contact with (14).

Next, the stylus (11
) is composed of electrode pads (1) formed along a pair of short sides of a semiconductor wafer chip (13), as shown in FIG.
4) are arranged so as to be in contact with.

That is, a tip is provided in the center of the substrate (2), a plurality of stylus needles (11) are arranged so as to be arranged substantially in a fan shape or in a radial direction, and are brought into contact with the stepped portion (15) and fixed with epoxy resin (15a). Furthermore, the fixed end is fixed to the electrically conductive part on the back surface (7b) of the board (2) with solder or the like. Therefore,
The stylus (11) can come into contact with the electrode pads (13a) formed along the pair of short sides of the semiconductor wafer chip (13), making it possible to conduct to the tester (not shown) side. Become.

Here, the length (L) of the cantilever support of the stylus (1) provided on the blade (10) and the length from the step (15) of the stylus (11) with one end fixed to the back surface (7b). It is made up of the same length as L. Furthermore, a protection plate (16) is provided on the front side of the board (1) to protect the printed wiring electrode surface and circuit surface to which the blade is fixed. Here, this protection plate (16) is illustrated by a chain double-dashed line in FIG.

Next, the effect will be explained.

When measuring a semiconductor wafer chip, for example a DRAM chip (13) of 1M or more, with the above substrate (2),
A probe card 0 corresponding to each electrode pad position of this DRAM (DRAM) of 1M or more is fixed to a fixed part. For example, a DRAM wafer chip of 1M or more is aligned under a fixing part on the bottom surface of a ring insert of a semiconductor wafer prober and this fixing part.

The wafer chip has a mounting table (not shown) for a semiconductor wafer prober, and this mounting table is raised and lowered to bring it into contact with the probe card 0. In this probe card 0, a stylus (11) provided on the back surface (7b) connects to electrode pads (13a) formed on the periphery of a pair of short sides of the wafer chip.
come into contact with.

Further, the stylus 0 provided on the surface (7a) of the probe card (2) contacts the electrode pad (14) formed at the center of the wafer chip.

The effect of this embodiment is that although the electrode pads formed on the periphery of the semiconductor wafer are brought into contact with the stylus (11) on the back surface (7b) of the substrate (2), the electrode pads formed at the center position of the semiconductor wafer chip (13) are The electrode pad (14) is attached to the surface (7) of the substrate (2).
The blade (10) fixed to a) is brought into contact with the stylus (9).

The lengths of the above two types of stylus (9, 11) are the same 4
Since the lengths are the same, the amount of deflection of the stylus (9, 11) is the same, so the life, stylus pressure, and contact resistance of the stylus (9, 11) are approximately the same.

In addition, the variation in the height of the stylus, the trace of the stylus relative to the position accuracy electrode pad, the contact resistance of the stylus, the inductance, the insulation resistance, the conductor resistance of the stylus, the capacitance, and the introduction angle of the stylus are all approximately the same. This makes it possible to perform highly accurate measurements.

Here, as the material of the stylus (9, 11), tungsten, baladium, beryllium steel, Parinek (trade name), etc. are used.

Further, as the material of the blade (10), ceramic members are often used.

〔Effect of the invention〕

Multiple stylus needles were arranged and fixed on the back side of the opened printed circuit board, and both stylus needles were placed on the blade with the proximal end of the stylus fixed on the surface. It has the effect of being able to be placed in any position.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram for explaining one embodiment of the probe card of the present invention, and FIGS. 2(a) and 2(b) show the positional relationship between the probe card of FIG. 1 and the electrode pads of the semiconductor wafer chip. FIG. 3 is an explanatory diagram for explaining the state in which the stylus is fixed to the blade of FIG. 1, and FIG. 4 is an explanatory diagram for explaining the conventional probe card. 6... Probe card 7... Board (printed circuit board) 9... Stylus (stylus fixed to the blade side) 10...
Blade 11... Stylus (stylus with one end fixed on the back side) 12...
Connection portion 13... Semiconductor wafer chip 13a... Electrode pad 14... Electrode pad (electrode pad formed in the center of the wafer chip) Patent applicant Tokyo Electron Ltd. 2nd (a)

Claims (1)

[Claims] In a probe card in which a plurality of stylus needles are arranged and fixed in a fan-shaped direction on the back side of an open printed circuit board, a blade having a proximal end of a stylus having the same length as the stylus fixed to the probe card is attached to the printed circuit board. A probe card characterized by being provided on the surface of.