JPH11330147A - Inner-lead bonding device used in tcp-type semiconductor device and inner-lead bonding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform stable bonding by providing the means which detects the thickness of a semiconductor chip and the bonding load, and controlling the bonding load through control means. SOLUTION: The position alignment of a carrier tape 2 and a semiconductor chip 4 is performed by a position detecting mechanism and a control device. The thickness of the semiconductor chip 4 is detected over a device hole 11 by a laser displacement meter 10. Then, a loading tool 5 is lowered in alignment with the positions of the semiconductor chip 4 and the carrier tape 2, and an inner lead 1 and a bump 3 are pushed and attached. The lowest point of the bonding tool 5 is computed from the thickness of the semiconductor chip 4 detected by the laser displacement meter 10 and the appropriate crushed amount of the bump 3, and the bonding load is detected. Based on this detected bonding load, the load is controlled by the control device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a TCP (Tape)
The present invention relates to an inner lead bonding apparatus used for manufacturing a carrier package type semiconductor device.

[0002]

2. Description of the Related Art FIG. 2 shows a method of positioning a semiconductor chip 4 having bumps 3 formed below a carrier tape 2 having inner leads 1, and pressing the inner leads 1 against the bumps 3 with a bonding tool 5 from above to perform thermocompression. 2 shows a configuration of a main part of a lead bonding apparatus. FIG. 3 is a conceptual diagram of a joint at the time of inner lead bonding. In order to ensure the quality of the semiconductor device, the bonding state between the bump 3 and the inner lead 1 is very important. For this reason, a constant load method for controlling the bonding load with high accuracy has been employed. FIG. 4 shows the relationship between the height of the bonding tool and the time during bonding. The bonding tool which is always at point a descends at a high speed to point b by the start of the bonding operation,
Thereafter, it descends at a low speed until the inner lead 1 and the bump 3 come into contact at the point c. After the inner leads 1 and the bumps 3 come into contact with each other, a constant load is continuously applied, and after a certain time, the bonding tool 5 rises at a point d. Conventionally, as a method of making the bonding load constant, a method of performing feedback control using a signal from a pressure detection device such as a load cell directly connected to a bonding tool, or a method of applying a constant pressure using an air cylinder having a small sliding resistance. Pressurizing method has been adopted.

[0003]

In the constant load method for making the bonding load constant, the contact area between the bump and the inner lead slightly changes or the hardness of both changes due to a slight displacement at the time of positioning. In such a case, there is a problem that the amount of crushing of the bump after the compression is changed. In addition, there is no major problem when the bond load exceeds several kilograms, but there is the following problem when the load is as small as less than 1 kilogram. (1) Since the magnitude of the sliding resistance of the guide and the cylinder approaches the magnitude of the bonding load, highly accurate load control cannot be performed. (2) S / S of pressure detection device used for feedback control
The N ratio deteriorates, and high-precision load control cannot be performed.

[0004]

FIG. 1 shows an embodiment of the present invention. The bonding tool 5 is mounted on a tool holder 7 directly connected to a load cell 6, and the load cell 6 is fixed to a vertical drive block 9 driven up and down by a vertical drive motor 8 with high accuracy. Further, a laser displacement meter 10 for accurately measuring the thickness of the semiconductor chip 4 is fixed to the tool holder 7. The position of the above mechanism is controlled by a position detection mechanism and a control device (not shown).

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail. (1) The carrier tape 2 and the semiconductor chip 4 are aligned by a position detecting mechanism and a control device not shown in the drawing. (2) Device hole 11 by laser displacement meter 10
The accurate thickness of the semiconductor chip 4 is measured. (3) Lower the bonding tool 5 in accordance with the positions of the semiconductor chip 4 and the carrier tape 2 and
And the pump 3 are crimped. At this time, the bonding tool 5
Is determined by the following method. (A) The lowest point of the bonding tool 5 is calculated from the thickness of the semiconductor chip 4 measured by the laser displacement meter 10 and the appropriate amount of crushing of the bump 3. (B) Set a theoretical load value that gives the bump 3 an appropriate amount of crushing in the control device. (C) The bonding tool 5 is lowered to the lowest point obtained in (a). However, when the theoretical load value set in (b) is reached during the lowering, the lowering of the bonding tool 5 is stopped with that point being the lowest point. (D) In low-load bonding where load detection becomes unstable, load detection is not performed, and the bonding tool 5 is lowered to the lowest point obtained in (a). That is, the present method is a method in which the constant crush amount method and the constant load method are combined. Although FIG. 1 shows the case where the laser displacement meter moves integrally with the bonding tool, a method of measuring the thickness of the semiconductor chip externally (not shown) may be adopted. It is also possible to use another thickness measuring device instead of the laser displacement meter.

[0006]

The effects of the present invention described above are listed below. (1) Excessive crushing of bumps, which is a problem in the case of the constant load method, is eliminated. (2) Stable bonding can be performed in low-load bonding that is easily affected by the sliding resistance of a guide, a cylinder, and the like, and the S / N ratio of a pressure detection device.

[0007]

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an inner lead bonding apparatus according to the present invention.

FIG. 2 is a diagram illustrating a conventional inner lead bonding apparatus.

FIG. 3 is a conceptual diagram of inner lead bonding.

FIG. 4 is a diagram showing a relationship between the height of a bonding tool and time during inner lead bonding.

[Explanation of symbols]

1 inner lead 2 carrier tape 3
Bump 4 Semiconductor chip 5 Bonding tool 6
Load cell 7 Tool holder 8 Vertical drive motor 9
Vertical drive block 10 Laser displacement meter 11 Device holes a, b, c, d Points indicating the position of the bonding tool

Claims (2)

[Claims] An inner lead bonding apparatus for manufacturing a TCP type semiconductor device, wherein after positioning a carrier tape and a semiconductor chip, an inner lead on the carrier tape is thermocompression bonded to a bump on the semiconductor chip by a bonding tool. Means for detecting the thickness of the chip is provided. (2) A means for detecting a bonding load is provided. (3) A control means for controlling the bonding load is provided. An inner lead bonding apparatus having the above configuration. 2. An inner lead bonding method in which, after positioning a carrier tape and a semiconductor chip, an inner lead on the carrier tape is thermocompression-bonded to a bump on the semiconductor chip by a bonding tool. Measure. (2) A bonding tool lowering position and a theoretical bonding load corresponding to the optimum bump crush amount are calculated from the measured semiconductor chip thickness and preset bump information. (3) Inner lead bonding is performed at the bonding tool descending position or the theoretical bonding load corresponding to the optimum bump crush amount. (4) In particular, when the theoretical bonding load is about 1 kilogram weight or less, the inner lead bonding is performed at the bonding tool descending position corresponding to the optimum bump crushing amount regardless of the theoretical bonding load. An inner lead bonding method characterized by performing the above procedure.