JPS6286826A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To reduce pure water on a chip by leaving a hydrophilic film such as a silicon oxide film on a dicing line. CONSTITUTION:A hydrophilic film 3 (e.g., a silicon oxide film, etc.) is left on a dicing line 1 which is used when a wafer is divided into chips. When the wafer is pulled up from a washing bath, water on the chip flows downward along the film 3 by gravity. This reduces the pure water on the chip.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a semiconductor device.

[Conventional technology]

FIGS. 8 and 4 show the manufacturing process of a conventional semiconductor device. This is a fr side view, in which (1) is a dicing (scribe) line for dividing the cube into chips, and (2) is one chip (the broken line indicates details are omitted).
, (3) is a silicon oxide film, and (4) is a silicon substrate. FIG. 4 shows a diagram in which an oxide film that is no longer needed before FIG. 2 has been removed, or an oxide film has been removed because it is necessary to expose the silicon substrate in relation to the next operation. 6th
The figure shows Ueno 1, and in the figure (1) is
The dicing line (2) shows one chip, and (5) shows a wafer. FIG. 6 shows the state in which the silicon oxide film was removed by wet processing in the process between FIG. 8 and FIG. 4, and then washed with water and the wafer was pulled up. (6) shows how pure water repels hydrophobic silicon and remains on the hydrophilic silicon oxide film due to surface tension.

FIG. 7 shows an apparatus for drying a wafer by shaking off water on the wafer using centrifugal force. (5) is the wafer, (7) is the Basquera for putting the wafer in, (8) is the centrifugal dryer body,
(9) indicates 1 exhaust/drain port, αq indicates the motor, and Qη indicates the lid.

Next, the operation of the prior art will be explained. For mass production of semiconductor integrated circuits (ICs), individual semiconductor elements are formed as shown in FIG. After that, a dicing line (scribe line) (1
) is divided into chips (2) and assembled.
In the process, the package is soldered and the IC is completed.

FIGS. 8 and 4 are cross-sectional views of a wafer showing a part of the process of forming semiconductor elements in an IC. In (2), one chip (1) is a dicing line.

A part of the semiconductor element is formed before FIG. 8, and the next process starts after FIG. The silicon oxide film that is no longer needed in FIG. 8 needs to be removed for work required in the next process.

At this time, the silicon oxide film on the dicing line around the chip is usually completely removed, exposing the silicon substrate. When removing this silicon oxide film, wet processing may be performed and cleaning with pure water may be performed. At this time, there is a lot of hydrophilic silicon oxide film inside the chip, and the area around the chip is hydrophobic silicon. , water remains on each chip due to surface tension.1 As shown in Figure 7, there are currently many methods of drying this water by using centrifugal force to shake off the water rather than rotating the wafer. It will be done.

[Problem that the invention seeks to solve]

Since the conventional semiconductor device manufacturing method is configured as described above, pure water remains on the chip, and in order to shake off this water, the rotational acceleration of the centrifugal dryer shown in Fig. 7 is increased. Another problem was that it required a long time. Further, as the diameter of the wafer becomes larger, the amount of pure water remaining on the chip increases, which increases the problem. Further, as the diameter of the wafer increases, the weight of the wafer increases, so if the rotation speed is increased, problems such as the wafer getting stuck in the basket arise.

This invention was made in order to solve the above-mentioned problems, and it is an object of the present invention to obtain a method for manufacturing a semiconductor device in which as much pure water as possible on the surface of one wafer is removed before using a centrifugal dryer. With the goal.

[Means for solving problems]

The method for manufacturing a semiconductor device according to the present invention leaves a hydrophilic film such as a silicon oxide film on the dicing line during the manufacturing process.

[Effect]

In this invention, when a hydrophilic film such as a silicon oxide film remaining on a dicing line is pulled up after the wafer is washed with water, the pure water on the chip is transferred by gravity through the hydrophilic film on the dicing line. The pure water gradually flows down to the lower chip, and the amount of pure water on the chip decreases.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a cross-sectional perspective view of the wafer. FIG. 2 is a sectional view. In FIGS. 1 and 2, (1) is a dicing line, (2) is a chip, and the semiconductor elements formed in the chip are omitted. (3) is a silicon oxide film that is present in large quantities in the chip, and (4) is a silicon substrate that forms one wafer. Figure 2 shows the state before removing the unnecessary silicon oxide film, and Figure 1 shows the state after removing the unnecessary silicon oxide film. (This is a cross-sectional view seen from the direction.) Wafer process process (semiconductor integrated circuit (IC) is placed on the wafer.
), in the normal photolithography process, there is often either resist all over one dicing line or no resist at all on one dicing line.At this time,
If the photoengraving process mask (retake lv) is partially cut out or light-blocked from the part corresponding to the dicing line, a hydrophilic film (e.g. (silicon oxide film) can be left behind.

For example, as shown in Figure 6, if the chip is surrounded by a hydrophobic material (silicon), when the wafer is lifted up after washing, the water on the chip will not flow down the wafer due to gravity. It accumulates on the chips and makes it difficult to dry in a centrifugal dryer, but as shown in Figure 1, if there is some hydrophilic material (silicon oxide film) on the dicing line (or even all of it), the wafer When the chip is lifted from the washing tank, the water on the chip flows down by gravity through this silicon oxide film, making it easier to dry.

In the above embodiment, a silicon oxide film is used as a bridge between chips, but other hydrophilic materials such as a silicon nitride film may be used.

Further, although this is related to etching an unnecessary oxide film, it can also be applied when light etching a natural oxide film using oxidizing acid.

〔Effect of the invention〕

As described above, according to the present invention, the pure water remaining on the wafer after washing can be removed by gravity as much as possible, so there is no need to particularly increase the rotational acceleration or rotational speed when drying with a centrifugal dryer. This has the effect of saving time. This becomes more effective as the diameter of the wafer increases.

[Brief explanation of drawings]

1 and 2 are cross-sectional views showing a method for manufacturing a semiconductor device according to an embodiment of the present invention (FIG. 1 is a perspective view, and FIG. 2 is a side view); FIGS. FIG. 5 is a plan view of a wafer; FIG. 6 is a side sectional view showing a wafer taken out of a washing tank after being washed with water in a conventional semiconductor device manufacturing method; FIG. 7 is a sectional view of the centrifugal dryer. (1) is a dicing line, (2) is a chip, (3) is a silicon oxide film, (4) is a silicon substrate, (5) is an unino, (6) is pure water, (7) is a basket for unino,
(8) is the centrifugal dryer, (9) is the exhaust/drain port, αO is the motor, and (b) is the lid. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] A method for manufacturing a semiconductor device characterized by leaving a hydrophilic film (for example, an oxide film, etc.) on a dicing (scribe) line used to divide a wafer into chips in the semiconductor device manufacturing process.