JPS5886743A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To separate a substrate into pellets in good yield by melting the solder electrode layer of the back surface of the substrate along a pattern, simultaneously attracting, removing the layer to expose the back surface electrode in a lattice shape and cutting the substrate. CONSTITUTION:A laser light 7 having the prescribed width is emitted from the emission port 6 of a laser generator onto a solder layer 3. A glass attracting tube 8 of conical shape is mounted on the end of the port 6, thereby communicating with a suction pump through a branch tube 8a and a tube 9. An in-desk base which places the laser generator or a substrate 1 is moved to move the aiming point of the light 6 along the scribing line 5 of the lattice pattern of the substrate 1, and the layer 3 is attracted and removed from the port 8b while melting the layer 3. In this manner, the solder can be readily removed, no clogging of a dicing blade occurs in case of separating the pellets, the separation can be facilitated, and no improper breakage occurs.

Description

[Detailed Description of the Invention] In this invention, a solder layer is formed on the top of the fourth layer and the next half is mounted.
This is related to 'J yta 7f pump.

When attaching semiconductor pellets to a stem or lead frame by brazing, most people who press the pellets onto the molten solder will not have surface ridges due to the numerical ratio or 7 lux V embossment in the gIIIK solder table 1. contact t-4
Therefore, an operation to destroy the C is required, which deteriorates productivity. A method called the pellet pre-soldering method has been considered, in which the solder is melted separately in the state of contact.

When a solder layer is formed on a semicircular semiconductor wafer to obtain such pellets, the solder layer is soft and relatively thick, so the semiconductor wafer has a lattice shape. When X1U is separated into Teheret,
The dicing grade used for cutting tends to become clogged and the cutting becomes inferior to 1.11, and the surface of semiconductor wafer ui+
From 1llll to halfway along the division! 4? Even with the method of breaking the cedar in one state, the 4R planes in the solder layer portion are likely to be uneven, resulting in so-called avec defects. - 10,000, this is 24 gold.
Eha's half-humiliated dog friend's division IV! l-
A solution has been proposed to form a portion along which no solder layer exists, but this solution is one of the problems with soldering between metal and half-metal, for example silicon. -Using the difference in nineness to prevent T-beam solder from adhering to silicon products, we removed the ohmic tray Y4 by etching it in a lattice pattern with the very common 4-toge carving process. This invention is aimed at improving the above-mentioned conventional deficiencies, and it is necessary to turn the semiconductor After forming a solder layer of a predetermined length on the entire surface of the electrode side, the wave is divided into pellets.

1v! By melting the solder mt in a lattice-like pattern and removing it by suction, the wax surface is exposed in a lattice pattern, and then the transparent solder is removed.
Cut the semiconductor wafer from the kJ-pole and divide it into pellets.
〇The method of the present invention will be explained below with reference to the drawings.
As shown in FIG. 7, a solder layer (3) is formed on the surface of the semiconductor wafer filO made of ohmic gold Tl4- (21) with a constant Pfr.
4) should be divided into sections! The pellet units (4) each include a target semiconductor element unit, and the division lines (5) of the Matomo pellet units (4) are in a grid pattern. Next, the solder layer (3) is melted in a predetermined width along the t-dividing line (5), and the molten solder is immediately removed by suction, and the surface '4 pole (21 surface is・After that, cut the 4 side electrodes of the grid pattern according to the '@ arrows, and make the 3rd
Separating into pellet units (4) as shown in the figure 〇 As mentioned above, there are methods for melting and removing the entire solder layer 13) in a lattice pattern. The convenience of an integrated device is preferred, hereinafter referred to as II.
An example will be explained with reference to all the drawings.

The diagram shows an example in which laser light is used to melt the solder layer (3). In the figure, (6) is the radar light irradiation port of the radar generator (illustration flag), and (7) is the half 11] mm i
On l+, the specified seaweed and the rede light gold sprinkled on tΦyotsu are shown. A suction α (8) made of conventional quartz or lath cedar is attached to the tip of this radar light irradiation port (6). This suction pipe (8) is a branch pipe (8a) that includes a suction pump with a drain tank (not shown) and a tube (9).
) K is sewn through 4 stitches, and a solder suction port (8b) 2 is provided at a position corresponding to the black leather of the lede light (7) at the tip. This device i! When using in the summer, the light of Rede light (7)
The radar generator 1 is placed so that the 14 points are along the sections of the grid pattern of half 4 pieces/%111.
Side or half 4 bodies Eha Ill t-extinct index table (not shown) lab young, half! B layer fat
While melting with the T-laser beam (7), open the solder suction port (8b).
) to remove the molten solder by suction.

The embodiment shown in figure @j uses a heater to melt the solder di31. In the aj diagram, 1101 is '
la @ (IOIL) is a solder lever-shaped heater with a pointed nine-shaped metal, and an opening (lot) at the tip (10 tortoise)) 1
In addition, the melted solder generated by contact with tip 4 (10a) is passed from the opening (lot) to the passage (lot) provided inside the heater HOI.
10a) and the tube (b) connected thereto are constructed so as to be removed by suction. The transition (1) of the melting point is performed by operating the heater Uυ or the stage (not shown) of the semiconductor wafer 111 at @1111al4.

The embodiment shown in FIG. 5 uses a heater like the example in FIG.
The solder layer (
3) The oblong tip (12a) is completely present so as to melt the solder at once, and the molten solder also flows through the slit-shaped opening (], 2t)) formed at the tip (12a).
120) and is removed by suction through tube ns2.

In addition, in this invention, melt 111! According to the method of the present invention, the solder layer to be removed (4 in 33 is determined by the design of the semiconductor package, but is usually 50 to 600 μm in diameter). Since the solder layer formed on the side electrode side can be removed extremely easily along the grid pattern that divides the semiconductor quadrature into pellets, it is difficult to remove the solder layer formed on the surface electrode side.
Separation is very d) A without causing cracking or damage due to breakage, and as a result, a semiconductor device with a solder layer entirely formed on the back side can be provided at low cost and with dMi.

[Brief explanation of the drawing]

Stone/Figures to 1263 show the manufacturing method of the semiconductor % filter of this invention in the order of steps, and Figure 7 is a cross section rTJ diagram of a four-body Aha with a solder layer formed on the entire back surface, and Figure 2 is a section I! ll
A cross-sectional view of the semiconductor quafer from which the solder layer RAM has been removed along the line, Figure 1g3 is a cross-sectional view of a pellet separated from the semiconductor quafer, and Figures Q, %g to Figure 6 all show the solder in the embodiment of this invention. It is a perspective view showing the melting and removal process of the layer 11)... semiconductor wafer, (2)... relative surface electrode, (
11...Solder layer, (4)...Bellet unit, (!I)...
- Grid pattern dividing lines. Figure 1 Prefecture-2 Figure 3 Darkness

Claims (1)

[Claims] 11) Semiconductor quay with a large number of children t+V/~, so ゛4 has a predetermined number of half tll on the entire surface of side 1)m
After forming the pellet, melt it with a low tPfr x 6 along the lattice-like pattern to divide it into pellets, and remove the rd, a and half 1 + J i by suction and train it in a grid pattern.
Manufacture of semiconductor devices by exposing semiconductor wafers and cutting the semiconductor wafer C from the quadrupole surface exposed in 4 above and separating it into pellets.