JPH01205442A - How to divide semiconductor elements - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] Regarding the improvement of a method for dividing a semiconductor element formed on a crystal substrate, the present invention relates to an improvement in a method for dividing a semiconductor element formed on a crystal substrate. The purpose of the present invention is to provide a method for dividing a semiconductor element that can prevent the occurrence of deformation, and to divide the crystal substrate into the semiconductor elements by dry etching, without depending on the crystal orientation of the crystal substrate on which a plurality of semiconductor elements are formed. The structure includes the step of further applying a protective film to the wall surfaces of the dividing grooves formed in the crystal substrate by dividing or dry etching.

[Industrial application field]

The present invention relates to a method for manufacturing a semiconductor device, and particularly to an improvement in a method for dividing semiconductor elements formed on a crystal substrate.

In the manufacture of semiconductor devices, various problems occur when dividing a semiconductor element formed on a crystal substrate into individual semiconductor elements.

For example, in GaAs devices, semiconductor elements are usually formed on the (1,0,0) plane, and then scribed using a diamond tool using the cleavage plane (0,1,11) to divide the semiconductor elements into individual semiconductor elements. ing.

Since the crystallinity of the crystal %4& is used in this way, when the cleavage plane of the crystal substrate and the scribe line of the mask are misaligned during the first mask alignment, the direction of the cleavage plane is This makes it difficult to scribe, and chips tend to occur around semiconductor devices when dividing into semiconductor devices.

Under the above circumstances, there is a need for a method for dividing a semiconductor element that does not cause chips on the dividing surface around the semiconductor element.

[Conventional technology]

A conventional method for dividing a semiconductor device will be explained with reference to FIGS. 4 to 5M.

During the first alignment of the mask to the crystal substrate 2], if the direction of the cleavage plane of the crystal substrate 2] matches the direction of the scribe line of the mask, the semiconductor element 2], a
Since the dividing groove and the crystal direction coincide with each other, it is possible to accurately divide the semiconductor element -2= as shown in FIG. 4 ta+.

However, since the semiconductor element 21a is divided using the crystallinity of the crystal substrate in this way, if the direction of the cleavage plane and the direction of the scribe line deviate during the first mask alignment, As shown in FIG. 4 fb), the dividing groove of the semiconductor element 2], a does not match the crystal direction, making it difficult to accurately divide the semiconductor element 21a. As shown in FIG. 5, when doing so, chips are likely to occur in the surrounding area.

[Problem to be solved by the invention]

In the conventional semiconductor device dividing method described above, the cleavage plane is used as the dividing groove, so during the first mask alignment, the direction of the cleavage plane and the direction of the scribe line are aligned. If there is no match,
In either case, there is a problem in that chips are likely to occur around the semiconductor element.

In view of the above-mentioned circumstances, the present invention provides a method for dividing a semiconductor element that can prevent chips from occurring around the semiconductor element when dividing the semiconductor element through a simple and easily implementable process. The purpose is to provide

[Means to solve the problem]

The problem in point 1 is that each crystal substrate is divided into semiconductor elements by dry etching, or semiconductor elements are formed on a crystal substrate by this dry etching, regardless of the crystal orientation of the crystal substrate on which a plurality of semiconductor elements are formed. This problem is solved by the method for dividing a semiconductor device according to the present invention, which further includes the step of depositing a protective film on the wall surface of the dividing groove.

[Effect]

That is, in the present invention, a dividing groove is formed by dry etching in the dividing groove of a semiconductor element of a crystal substrate on which a plurality of semiconductor elements are formed, and the semiconductor element is divided into individual semiconductor elements by this dividing groove, or by this dry etching. Since the crystal substrate is further coated with a protective film on the wall surface of the dividing groove and then divided, it is possible to prevent the occurrence of chips around the divided semiconductor elements.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3 in the case where the dividing groove has a metal layer.

FIG. 1 is a side cross-sectional view showing the main parts of the semiconductor element 1a near the dividing groove 5 formed on the crystal substrate 1 in the order of steps.

First, as shown in FIG. 1(a), a metal layer 1b is formed in the dividing groove of the crystal substrate 1''2 for protection during division, and wax 3 is applied to the entire surface of the element forming region 1c. The holding substrate 2 and the crystal substrate 1 are bonded together and integrated.

A silicon oxide film is formed on the entire surface of the crystal substrate 1 opposite to the element formation region 1c in this state, and as shown in the figure, the silicon oxide film at the dividing groove 5 is removed using a lithography technique, and a mask is formed. form 4.

Next, as shown in FIG. 1 tb+, using this mask 4, the crystal substrate 1 is etched and removed by plasma etching under the following conditions, dividing grooves 5 are formed, and the semiconductor element 1 is etched away.
Divide into a.

Reaction gas - Carbon tetrachloride (CCV, ) Ten oxygen (○Z) Reaction gas flow rate (CCf' 4 ) -----
-------------50cc/min (○
=) −−−−−−−−−−−−−−−−−−40c
c/min Reaction chamber pressure----------------------
−−−−−−−−−−−−−−0, 1, Torr substrate heating temperature −−−−−−−−−−−−−−−−
−−−−−−−40°C high frequency power supply frequency−−−−−
=−−−−−−−−−−−−−−13, 5 leaf high frequency power output −−−−−−−−−−−−−−−−−−−−−−
100 W This etching rate is about 2 μm/min, and it is possible to form the dividing grooves 5 by etching regardless of the crystal direction of the crystal substrate 1.

Next, as shown in the first view (C), the metal 1ilb is removed by ion milling to completely form the dividing grooves 5, and then the mask 4 is removed.

Finally, as shown in FIG. 1 (d+), a protective film 6 is formed by vapor depositing a metal, for example, gold, on the side surfaces of the dividing grooves 5 formed in the crystal substrate 1 and the back surface of the crystal substrate 1. In addition to gold germanium (AuGe), it is also possible to use gold germanium (AuGe).

The area around the semiconductor element 1a is protected by this protective film 6,
It is possible to prevent the occurrence of chips or the like around the semiconductor element 1a during handling.

FIG. 2 shows a side sectional view of a crystal substrate after processing according to an embodiment of the present invention. In this state, the wax 3 is dissolved with an organic solvent such as 1 to Recurne, and the semiconductor element 1a and the holding substrate 2 are separated and divided into individual semiconductor elements 1a.

As the material for the mask 4, it is also possible to use a silicon nitride film or a thin nickel film in addition to the above-mentioned silicon oxide film.

Etching of the dividing grooves 5 of the crystal substrate 1 is not limited to the above-mentioned method, but may also be plasma etching using a mixed gas of chlorine (α2) and hydrogen (H2) as a reactive gas, or using aluminum or the like with high spatter resistance as a mask. , ion milling, and reactive ion etching.

In another embodiment shown in FIG. 3, GaAs crystal groups Fj, 11
A semiconductor element formed on the plane orientation (LLI) is limited by the cleavage plane, and has a shape like b in the figure, but according to the present invention, the shape is like a in the figure, and it can be accurately It becomes possible to separate into

If the crystal substrate 1 is divided into semiconductor elements 1a by plasma etching, ion milling, or active ion etching, or if the protective film 6 is further formed on the divisions 45, the semiconductor elements 1a It is possible to prevent chipping around the area.

[Effects of the Invention] As is clear from the following explanation, according to the present invention, a semiconductor element formed on a crystal substrate can be separated without causing chips around it by a process that can be carried out extremely easily. It has the advantage that it is possible to do this, and can be expected to have the effect of significantly improving quality, making it extremely useful industrially.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing the main parts of an embodiment according to the present invention in the order of steps; FIG. 2 is a side sectional view without showing the crystal substrate after processing of an embodiment according to the present invention; FIG. 3 is a side sectional view showing the main parts of an embodiment according to the present invention. FIG. 4 is a plan view showing how a conventional semiconductor device is divided, and FIG. 5 is a perspective view of a semiconductor device divided by a conventional semiconductor device dividing method. In the figure, 1 is a crystal substrate, 1a is a semiconductor element, 1b is a metal layer, 1c is an element formation region, 2 is a holding substrate, 3
is wax, 4 is a mask, 5 is a dividing groove, and 6 is a protective film. The engraving of the drawings (al) The pasting of the holding substrate and the formation of the mask (bl)
Division by etching of the crystal substrate tel Division of the metal layer and removal of the mask Drafting of the drawing (d) Formation of the protective film Side cross-section drawing showing the main parts of an embodiment according to the present invention in order of T. Figure 1 An embodiment according to the present invention Fig. 2 is a side cross section showing the main parts of an embodiment according to the present invention as a step-by-step diagram; Fig. 1 is a plan view showing another embodiment according to the present invention; Fig. 3 is a conventional Figure 4: A perspective view of a semiconductor element divided by the conventional dividing method Figure 5: Procedural amendment (Method) June 1988/71] 1.1M cow display 1986 Patent Application No. 029257 2, Name of the invention: Method for dividing semiconductor elements 3, Relationship with the case of the person making the amendment Patent applicant address: 1015 Kamiodanaka, Nakahara-ku, Yozaki City, Kanagawa Prefecture Name (522) Fujitsu Limited

Claims (2)

[Claims] (1) A crystal substrate (on which a plurality of semiconductor elements (1a) are formed)
1) A method for dividing a semiconductor device, characterized in that the crystal substrate (1) is divided into the semiconductor devices (1a) by dry etching without depending on the crystal direction. (2) The crystal substrate (1) is formed by the dry etching.
2. The method for dividing a semiconductor device according to claim 1, further comprising the step of depositing a protective film (6) on the wall surface of the dividing groove (5) formed in the dividing groove (5).