JPS6181633A - Lead frame fixing device - Google Patents

Abstract

PURPOSE:To bond perfectly a wire to an inner lead by placing a wedge fastener between plural inner leads of a lead frame installed in a wire bonding device. CONSTITUTION:Inner leads 1-12 of a lead frame are mounted on the board 14 of a wiring bonding device. The inner leads 1-12 are fixed on the board 14 through being pressed to it by a presser plate 13. Each wedge tooth 15a of the said fastener 15 is embedded between each inner lead 1-12 with the wedge fastener in which plural wedge teeth 15a is arranged in U-shape to the inner lead, and is fixed through positioning the inner leads 1-12 in an exciting direction by the wire bonding device. Therefore, when the inner lead and the wire are bonded adding an ultrasonic oscillation, the wire can perfectly be bonded to all the inner leads.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a lead frame fixing device for a wire bonding device.

[Conventional technology]

When connecting the semiconductor chip and the inner lead of the lead frame with a wire on a lead frame with a semiconductor chip mounted on it, it is necessary to fix the inner lead so that it does not shift during work and cause a connection error. Figures 2(a) and 2(b) show a conventional method for fixing a lead frame, in which inner leads 1-12 of the lead frame are placed on a stand 14 of a wire bonding device, and a presser plate 13 is attached from above. The inner leads 1 to 12 are fixed on the stand 14 by pressing them evenly.

In general wire bonding, the table 14 of the bonding equipment is heated to around 350°C, a pure gold wire is used as the wire, and the wire is pressed against the semiconductor chip, inner leads, etc. under a load, and the wire is melted with heat. and glue.

However, when bonding a semiconductor chip to a lead frame, the temperature of the stage 14 of the bonding device must be low if a lifting stage is used that uses a brazing material with a low melting point, or if oxidation of the lead frame is a problem. Furthermore, if the wire is made entirely of aluminum, the aluminum surface will be covered with oxide even if the temperature is raised, so it will not be possible to bond the wire. In such cases, bonding is generally achieved by applying ultrasonic vibration to the wire.

[Problem that the invention seeks to solve]

In a typical wire bonding device 2, the direction of ultrasonic vibration is determined to be one direction due to the structure of the device. For example, when ultrasonic vibration is applied to inner reeds 5 to 8 and consonants in FIG. 2(a), inner reeds 1 to 4, 9
-12, vibration is applied in a direction perpendicular to the direction of the reed. In the inner leads 5 to 8, since the lead direction and the vibration direction are parallel, the lead frame is completely held down by the holding plate 13, and the wire and the inner lead can be completely bonded. However, inner leads 1 to 4
, 9 to 12, the lead direction and the vibration direction are perpendicular to each other, so the lead may be vibrated at the point held down by the lead frame holding plate 13 as a node, or if the lead frame is thick, it may be vibrated in a twisting manner. Much of the energy of the ultrasonic vibrations is wasted in this process. As a result, the adhesion between the wire and the inner lead was incomplete and the wire was damaged.The present invention provides a device that eliminates this drawback.

[Means for solving problems]

The present invention is a lead frame fixing device characterized in that a wedge jig is driven between a plurality of inner leads of a lead frame installed in a wire bonding device to regulate the position of the inner leads in the direction of vibration by the device. be.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In FIGS. 1(a), (b), and (C), the inner leads 1 to 12 of the lead frame are placed on the stand 14 of the wire bonding device, and the suppressing plate 13 is placed on top of the inner leads 1 to 12 of the lead frame.
The inner leads 1 to 12 are fixed on the stand 14 by pressing. Furthermore, a plurality of wedge extraction teeth 15a, 15a.
... are arranged in a U-shape in line with the inner leads, each wedge tooth 15a of the jig 15 is fitted between the valley inner leads l to 12, and vibration is applied by a wire bonding device. The positions of the inner leads 1 to 12 are regulated and fixed in the direction.

According to the embodiment, between inner leads 1-12:
Since the wedge teeth are driven in to regulate the lateral position of the inner lead, even when ultrasonic vibration is applied to the inner lead by the wire bonding device, the inner lead in the direction perpendicular to the imaging direction (1 in the figure) ~4,9~1
Even in 2), no vibration, twisting, etc. occur, and therefore, when bonding the inner lead and wire while applying ultrasonic vibration in a wire bonding device, the wire can be completely bonded to all inner leads. .

〔Effect of the invention〕

As explained above, the present invention regulates the positions of the plurality of inner leads of the lead frame, so that when bonding the inner leads and the wire while applying ultrasonic vibration to the inner leads, It has the effect of completely adhering the wire and inner lead without causing vibration or twisting.

[Brief explanation of drawings]

Are Fig. 1 (a), (b), and (c) an embodiment of the present invention? (a) is a plan view, (b) is the first
A cross-sectional view taken along the line Y-Y' in Figure (a), (C) is the same as in Figure 1 (a).
2(A) is a plan view showing a conventional example, and FIG. 2(b) is a sectional view taken along Y-Y' line of FIG. 2(a). 1 to 12... Inner lead of lead frame, 13
...Lead frame holding plate, 15...Wedge jig patent applicant NEC Co., Ltd. Figure 1 (α) 15------ <Sahi' jig (b) (C) (α) (b) “

Claims (1)

[Claims] (1) A lead frame fixing device characterized in that a wedge jig is driven between a plurality of inner leads of a lead frame installed in a wire bonding device to regulate the position of the inner leads in the direction of vibration by the device. .