JPH04139893A - Heating chip and mounting by using the same - Google Patents

Abstract

PURPOSE:To improve throughput, accuracy and an yield of tucking operation by holding adjustably a difference between reference surfaces of a heating chip according to mounting references. CONSTITUTION:Eight chips 1 are arranged around an LSI and tips thereof are in close contact with the edges of the LSI. Here, reference faces to the thickness and width directions of a heating chip are made to constitute A and B, and as to size accuracy of (a) and (b) in Fig., the reference faces of the chip 1 A and B and a reference at the time of mounting the chip 1 are combined to facilitate to ensure accuracy. Then, the ceramic chip 1 is held by a rail part of an LM(linear motion) guide 3 by means of a mounting frame 2, eight pieces of chips 1 are made movable in parallel vertically about 5mm so as to adjust a pressure amount at the time of tucking by a spring 4. Thereby, throughput, accuracy and an yield of tucking can be heightened.

Description

[Detailed Description of the Invention] [Summary] Tacking a heating chip and a semiconductor device onto a substrate
ing, temporary soldering).

The purpose of the present invention is to provide a tacking method that reduces the frequency of replacing heating chips, and has high throughput, high precision, and high yield.

1) A plurality of heating chips that contact and heat terminals of a semiconductor device and solder the terminals to a substrate, the heating chips having at least one of their constituent surfaces as a reference surface, and the reference of the heating chips. The heating chip has a holder that allows the distance between the surfaces to be adjusted according to the mounting standard of the heating chip.

2) Two heating chips are arranged on each of the four sides of the semiconductor device.

3) The heating chip is configured to be a ceramic chip.

4) When a heating chip is brought into contact with a terminal of a semiconductor device to heat the heating chip, melt the preliminary solder of the terminal, and tack the semiconductor device to a substrate, at least one surface constituting the heating chip is set as a reference surface. and the distance between the reference surfaces of the chips is adjusted in accordance with the mounting standard of the heating chip.

[Industrial application field]

The present invention relates to a method for mounting a heating chip and a semiconductor device.

In particular, the present invention relates to a method of tacking a semiconductor device to a substrate.

[Conventional technology]

When tacking a semiconductor device such as an LSI to a substrate,
Tacking was performed by directly applying a heating chip (heat source) to an LSI terminal, heating the chip, and melting the preliminary solder on the terminal.

Furthermore, conventional heating chips used a copper plate with a heater attached inside it.

[Problem to be solved by the invention]

The conventional example had the following problems.

■ Since the chip is heated to a high temperature, the width of the chip shape becomes wider due to thermal expansion, and on a board with a high packaging density, it is not possible to tack multiple LSI terminals at the same time, and single chips must be moved one after another. This requires time and tacking takes time.

■ It is difficult to ensure accuracy at the tip of the chip, and since there is no reference surface on the chip, it is difficult to ensure tacking accuracy, and the mounting yield is poor.

■ Tacking takes time because the chips cannot be heated instantly.

■ Chips deteriorate rapidly and have a short lifespan, so they must be replaced frequently.

SUMMARY OF THE INVENTION An object of the present invention is to provide a tacking method that reduces the frequency of replacement of heating chips and has high throughput, high precision, and high yield.

[Means to solve the problem]

What is the solution to the above problem?

1) A heating chip that comes into contact with a terminal of a semiconductor device to heat it and solder the terminal to a substrate, the heating chip having at least one of its constituent surfaces as a reference surface, and the reference surface of the heating chip. 2) a heating chip having a holder for the heating chip whose distance between the heating chips can be adjusted according to the mounting standard of the heating chip; or 2) a heating chip in which two heating chips are arranged on each of the four sides of the semiconductor device. 1) The heating chip as described above, or 3) The heating chip as described in 1) or 2) above, wherein the heating chip is a ceramic chip, or 4) The heating chip is brought into contact with a terminal of a semiconductor device to heat the semiconductor device. When heating the chip to melt the preliminary solder of the terminal and tacking the semiconductor device to the substrate, at least one surface constituting the heating chip is used as a reference surface, and the distance between the reference surfaces of the chip is determined as the heating chip. This is achieved through a mounting method that adjusts to the mounting standards of the industry.

[Effect]

The present invention uses a ceramic chip as a heating chip, has a small shape, and has at least one ceramic chip constituting the heating chip.
The positional accuracy of the heating chip can be ensured by using the surface as a reference surface.

FIGS. 1A and 1B are diagrams of the principle of the present invention, and are layout diagrams of heating chips (ceramic chips).

In the figure, eight chips 1 are arranged around the LSI, and their tips are in contact with the LSI terminals.

Here, A is the reference plane in the thickness direction of the heating chip, and B is the reference plane in the width direction of the heating chip.

In the figure, the dimensional accuracy of a is ensured by aligning the reference surface of the chip with the standard when attaching the chip, and the dimensional accuracy of b is ensured by aligning the reference surface B of the chip with the reference point when attaching the chip. It's easy.

Furthermore, by using a ceramic chip for the chip, instantaneous heating (4006 C/sec) is possible, shortening the tacking time and significantly extending the life of the chip.

The heating rate of conventional heating chips is 400°C/3 to 5 seconds, and the reason why the heating rate of ceramic chips is so fast is that the shape does not deform or the material deteriorates even if the temperature is raised rapidly. .

〔Example〕

FIGS. 2(a) and 2(b) are two side views of the ceramic chip used in the example.

In the figure, l is the chip body, and IA and IB are terminals for power supply.

Further, A and B are reference planes.

FIG. 3(b) is a block diagram of an embodiment of the present invention.

The figure shows the mounting structure of the ceramic chip.

The ceramic chip holder is constructed as follows.

The ceramic chip l is held on the rail part of the LM (linear motion) guide 3 by the mounting piece 2, and is
Eight ceramic chips of about mm can be moved in parallel.

Since the accuracy of tacking changes depending on the temperature of the chip, the heating time, and the amount of pressure applied, the amount of pressure applied during tacking is adjusted by the spring 4.

Further, the heating time and chip temperature are adjusted based on the chip temperature increase data.

FIGS. 4(a) and 4(b) are diagrams corresponding to the high-density mounting board of the embodiment.

When mounting an LSI on a high-density mounting board (reference pitch: 28 mm), this can be achieved by reducing the width dimension of the ceramic chip l (i.e., providing a widthwise relief at the tip).

The actual implementation after tacking is performed as follows.

Two chips (for example, Mo plated with Au.

The LSI is soldered onto the board using an autobonder (automatic soldering machine) whose tip is coated with ceramic by thermal spraying.

At this time, since the LSI is temporarily attached, place the chip on the LSI terminal based on the external shape of the LSI, heat it and solder it, then rotate the chip 90 degrees and repeat the same operation to solder in four directions. I do.

〔Effect of the invention〕

As explained above, according to the present invention, a tacking method with reduced chip replacement frequency, high throughput, high precision, and high yield was obtained.

As a result, high-precision LSI mounting has become possible with high yield and high throughput.

[Brief explanation of drawings]

FIGS. 1(a) and 1(b) are diagrams of the principle of the present invention, and are layout diagrams of heating chips (ceramic chips). FIGS. 2(a) and 2(b) are two side views of the ceramic chip used in the example. Figure 3 (al), (bl is a configuration diagram of an embodiment of the present invention. Figure 4 (aL) (bl is a diagram corresponding to a high-density mounting board of the embodiment. In the figure. ■ is a heating chip and a ceramic chip. IA , IB are terminals. A and B are reference planes. 2 is mounting piece 3 is LM guide. 4 is spring percentage 3.', 5 (α) Top view ((1) Top view (α) Old eyes [] [HI

Claims (1)

[Scope of Claims] 1) A plurality of heating chips that contact and heat terminals of a semiconductor device and solder the terminals to a substrate, the heating chips having at least one of the constituent surfaces as a reference surface; A heating chip characterized in that it has a holder for the heating chip that can adjust the distance between the reference surfaces of the heating chip in accordance with the mounting standard of the heating chip. 2) The heating chip according to claim 1, wherein two heating chips are arranged on each of four sides of the semiconductor device. 3) The heating chip according to claim 1 or 2, wherein the heating chip is a ceramic chip. 4) When a heating chip is brought into contact with a terminal of a semiconductor device to heat the heating chip, melt the preliminary solder of the terminal, and tack the semiconductor device to a substrate, at least one surface constituting the heating chip is set as a reference surface. and adjusting the distance between the reference surfaces of the chips in accordance with the mounting standard of the heating chip.