JPS5856356A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To make a hole on an insulating film on the first conductor with high accuracy, and to prevent the displacement of the mask alignment of an opening section and a conductor wiring layer by forming the first pattern with the first opening to a photosensitive resin film formed onto the insulating film. CONSTITUTION:A reverse conduction type impurity is diffused to one conduction type silicon semiconductor substrate 10, and the first conductor layer 11 is formed selectively. The insulating film 12 and the first photosensitive resin film 13 are shaped to the whole surface, and the opening section 14 is formed to the film 13. The first photosensitive resin film 13 is baked, and the second photosensitive resin film 15 is shaped to the whole surface. The pattern 15' is formed to the second photosensitive resin, and the insulating film 12 is exposed in a crossing section. The insulating film 12 is removed through etching and the opening section 16' is molded, and the first photosensitive resin film 13 is removed. The second conductor layer 17 is formed, followed by the shaping of the third photosensitive resin 18.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a semiconductor device, and provides a method for forming an opening in an insulating film and a wiring layer pattern, which requires a small number of masks and can achieve high density.

FIG. 1 shows a conventional method for forming an opening in an insulating film and a wiring pattern in the manufacturing process of a semiconductor device. A semiconductor substrate 1 and a conductive layer 1 formed therein.
An insulating film 2 and a photosensitive resin film 3 are formed thereon, and ultraviolet rays are selectively irradiated using a hole-forming photomask to form predetermined openings 4 in the resin film 3 (step 3). The insulating film 2 is etched using the photosensitive resin film 3 as an etching mask to form an opening, and then the photosensitive resin film 3 is removed. After forming the conductive layer 5 and the photosensitive resin film 6 on the entire surface, a photosensitive resin film pattern 6' is formed using a photomask having a wiring layer pattern (B). Photosensitive resin film pattern 3.

After etching the conductor layer 6 using the conductor layer 6 as an etching mask, the photosensitive resin film is removed to form a wiring layer pattern 7 connected to the conductor layer 1. (Mu・), (C・) is (Mu),
It is a figure which shows the plane pattern of (C).

This method requires two types of photomasks: a photomask for forming the opening and a photomask for forming the wiring layer.

Also, after removing the photosensitive resin film 3 for forming the opening, a new photosensitive resin film 6 for forming the wiring layer is formed.

The positioning accuracy of the opening and the wiring layer pattern is required, and an alignment margin l is required, which hinders high density.

Furthermore, as the width of the opening becomes smaller, a pattern faithful to the photomask cannot be formed due to light diffraction development, resulting in rounded corners.

The present invention provides a method in which holes are formed in an insulating film with high precision, and there is no misalignment between the holes and the conductor wiring layer.

An embodiment of the present invention will be described with reference to FIG.

- selectively forming the first conductor layer 11 by diffusing, for example, an opposite conductivity type impurity into the conductivity type silicon semiconductor substrate 10;

An insulating film 12 and a first photosensitive resin film 13 are formed on the entire surface (step 3). Openings 14 are formed in the first photosensitive resin film 13 using the first photomask used to form the first conductor layer 11.
(B). After baking the first photosensitive resin film 13, a second photosensitive resin film 16 is formed on the entire surface so that it is thicker than the first photosensitive resin film 13 and has a flat surface (C). .

Next, a pattern 16 is formed on the second photosensitive resin film using a second photomask having a pattern of a second conductive layer connected to the first conductive layer 11 (D). The insulating film 12 is exposed at the intersection 16 between the pattern of the first photosensitive resin film 13 and the second photosensitive resin film pattern 16.

Next, after etching away the insulating film 12 to form an opening 16 (X), the exposed first photosensitive resin film 13 is removed by oxygen plasma treatment or the like.

At this time, a part of the second photosensitive resin film pattern 16' is also removed, but since it is formed thicker than the first photosensitive resin film, the pattern 16 and the lower first pattern 6; The resin film 13 remains.

A second conductor layer 17 made of metal or the like is formed on the entire surface, and a third photosensitive resin film 18 is then applied to the remaining first and second conductor layers.
(F). Either by using the second photomask for forming the second conductive layer pattern, or by thinning the third photosensitive resin film over the entire surface as shown in FIG.
A third photosensitive resin film pattern 18' is formed only in the recessed areas other than the second photosensitive resin films 13' and 15. Next, using the pattern 18 as a mask, the exposed region of the second conductor layer is etched away to form a wiring layer pattern 17.

In the embodiment described above, the etching process of the insulating film 12 shown in FIG. The process up to the formation of layers can be performed continuously in a vacuum atmosphere.

Also, before forming the second conductor layer, the first and second connections 6,...
.

In order to reduce the resistance, the insulating film formed on the first conductor layer by oxygen plasma treatment may be removed in advance by solution or dry etching. In the above embodiment, the first conductor layer is used as the first photomask. A mask with a pattern was used, but the first and second
It goes without saying that another photomask may be used that intersects the second conductor layer pattern at the connection portion of the conductor layer.

Incidentally, as shown in (Second Fixation), the openings can be formed more accurately if a margin m is left in the longitudinal direction of the second conductor layer pattern 17'.

As described above, according to the present invention, the opening portion is
Since the conductor layer can be formed using a photomask for forming the conductor layer, a separate photomask for forming the opening can be omitted. Furthermore, since the corners of the opening are formed by two sides of different photomasks, the shape is not rounded. Further, since the formation of the opening and the formation of the wiring layer can be performed continuously, unlike the conventional method, high density can be achieved without requiring positioning.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining a conventional example, and (M) to (C) are structural sectional views, (M) and (C) are plan views of the states of (Ml and (C), respectively). FIG. 2 is a diagram for explaining the manufacturing process of a wiring pattern according to an embodiment of the present invention.
(M) to (H) are structural cross-sectional views, (B') and (D')
, (H.) is the same CB+, (D). It is a top view of the state of (H). 1o... Semiconductor substrate, 11... First conductor layer, 12... Insulating film, 13... First photosensitive resin, 14, 16 '...Opening part,
16...Second photosensitive resin pattern, 16.
...Intersection, 17...Wiring layer pattern. Name of agent: Patent attorney Toshio Nakao and one other person II
Figure 12 Figure 2 Procedural amendment form) March 1980 7F3 Director of the Japan Patent Office l Case display 1982 Patent Application No. 155587 2 Name of the invention Method for manufacturing semiconductor devices 3 Person making the amendment Relationship with '1 Patent application
Address: 1006 Kadoma, Kadoma City, Osaka Prefecture
Name (582) Matsushita Electric Industrial Co., Ltd. Representative Toshihiko Yamashita 4 Agent 571 Address 1006 Oaza Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. JP 58-56356 (4) Specification 1; Title of the invention: Method for manufacturing a semiconductor device 2, Claims (1) A first semiconductor device formed on an insulating film on a first conductor.
forming a first pattern having a first opening on the first conductor in the photosensitive resin film; forming a second photosensitive resin film from the first photosensitive resin film; forming a second pattern on the second photosensitive resin film having a second opening that intersects with the first pattern and the first opening; and a step of etching away the insulating film exposed at the intersection of the openings of the second pattern;
After etching away the exposed portion of the first photosensitive resin film and forming a second conductor layer on the entire surface, selectively removing the second conductor layer and removing the first conductor layer. A method for manufacturing a semiconductor device, comprising the step of forming a wiring pattern that is in contact with a body and corresponds to the second pattern. (2) First pattern formation 2/
, ~ The method of manufacturing a semiconductor device according to claim 1, wherein the same mask is used. 3. Detailed Description of the Invention The present invention relates to a method for manufacturing a semiconductor device, and provides a method for forming openings in an insulating film and wiring layer patterns, which requires a small number of masks and enables high density. FIG. 1 shows a conventional method of forming an opening in an insulating film and forming a wiring pattern in the manufacturing process of a semiconductor device. An insulating film 2 and a photosensitive resin film 3 are formed on the semiconductor substrate 1 and the conductive layer 1' formed therein, and the resin film 3 is selectively irradiated with ultraviolet rays from a photomask for forming an opening.
A predetermined opening 4 is formed in (A). The insulating film 2 is etched using the photosensitive resin film 3 as an etching mask to form an opening, and then the photosensitive resin film 3 is removed. After forming the conductive layer 5 and the photosensitive resin film 6 on the entire surface, a photosensitive resin film pattern 6' is formed using a photomask having a wiring layer pattern (B). 372. The conductor layer 6 was etched using the photosensitive resin film pattern 6' as an etching mask. - After removing the photosensitive resin film 6', a wiring layer pattern 7 connected to the conductor layer 1' is formed (Q, lll1?, (G) is (5), (Figure showing the planar pattern of Q) This method requires two types of photomasks: a photomask for forming the opening and a photomask for forming the wiring layer.Furthermore, after removing the photosensitive resin film 3 for forming the opening, a new photomask for forming the wiring layer is used. In order to form the photosensitive resin film 6', alignment accuracy between the opening and the wiring layer pattern is required, and alignment margin 2 is required.
This is an impediment to higher density. Furthermore, when the width of the opening becomes small, a pattern faithful to the photomask cannot be formed due to light diffraction development and the like, resulting in rounded corners. The present invention provides a method in which holes in an insulating film are formed with high accuracy and there is no misalignment of mask alignment between the holes and the conductor wiring layer. . An embodiment of the present invention will be described with reference to FIG. - selectively forming the first conductor layer 11 by diffusing, for example, an opposite conductivity type impurity into the conductivity type silicon semiconductor substrate 10; An insulating film 12 and a first photosensitive layer 41 are formed on the entire surface. . A synthetic resin film 13 is formed (5). Openings 14 are formed in the first photosensitive resin film 13 using the first photomask used to form the first conductor layer 11 (B). After baking the first photosensitive resin film 13, a second photosensitive resin film 15 is applied to the entire surface, which is thicker than the first photosensitive resin film 13.
Form the surface so that it is flat (Q. Next, using a second photomask having a pattern of the second conductor layer connected to the first conductor layer 11, the second photosensitive resin film is formed so that the surface is flat. (Q) The insulating film 12 is exposed at the intersection 16 of the pattern of the first photosensitive resin film 13 and the second photosensitive resin film pattern 16'. Next, the insulating film 12 is etched. After cutting and removing to form the openings 16' (E), the exposed first photosensitive resin film 13 is removed by oxygen plasma treatment or the like.At the same time, the second photosensitive resin film pattern 16 is removed. ' is also partially removed, but since it is formed thicker than the first photosensitive resin film, the first photosensitive resin film 13 below the pattern 15' is removed.
′ remains. (5) A second conductive layer 17 made of metal or the like is formed on the entire surface, and a third photosensitive resin film 18 is further applied to the remaining first and third conductor layers. It is formed thicker than the photosensitive resin films 13' and 15' of No. 2 (F
). Either by using the second photomask for forming the second conductive layer pattern, or by thinning the third photosensitive resin film over the strip surface as shown in FIG. A third photosensitive resin film pattern 18' is formed only in the recessed areas other than the photosensitive resin films 13' and 15'. Next, using the pattern 18' as a mask, the exposed area of the second conductive layer is etched away to form a wiring layer pattern 17'. In the above embodiment, the etching process of the insulating film 12 shown in FIG. The steps up to the formation of the conductor layer can be performed continuously in a vacuum atmosphere. Furthermore, before forming the second conductor layer, the insulating film formed on the first conductor layer may be removed by oxygen plasma treatment using a solution or dry etching in order to reduce the connection resistance between the first and second conductors. 0 In the above example, a mask having a first conductor layer pattern was used as the first photomask, but the first and second photomasks were
It goes without saying that another photomask may be used that intersects the second conductor layer pattern at the connection portion of the conductor layer and the conductor layer. Note that, as shown in FIG. 2(c), it is better to leave a margin m in the longitudinal direction of the second conductor layer pattern 17'.
The openings can be formed with high precision. In addition, (I), (J), (K) in the same figure are (B), (D)
, H is a diagram showing a plane pattern. As described above, according to the present invention, the opening portion is
Since the conductor layer can be formed using a photomask for forming the conductor layer, a separate photomask for forming the opening can be omitted. Further, the corners of the openings are not rounded because they are formed by two sides of different photomasks. Furthermore, since the formation of the openings and the formation of the wiring layer can be performed continuously, the alignment accuracy is improved unlike in the past, and high density is possible without requiring the alignment allowance as in the past. 4. Brief explanation of the drawings Figure 1 is a diagram for explaining the conventional example. , FIG. 2 is a diagram for explaining the manufacturing process of a wiring pattern according to an embodiment of the present invention, (6) to (c) are structural cross-sectional views, (I), (J), (I). ) is the same as (
f3), (D), (F() is a plan view of the state. 1o... Semiconductor substrate, 11... First conductor layer, 12... Insulating film , 13... 1st
Photosensitive resin, 14, 16'... Opening part, 15
'...Second photosensitive resin pattern, 16...
...Intersection, 17...Wiring layer pattern.

Claims (2)

[Claims] (1) Forming a first pattern having a first opening on the first conductor in the first photosensitive resin film formed on the insulating film on the first conductor. A second photosensitive resin film is applied thicker than the first photosensitive resin film, and a second photosensitive resin film is coated on the second photosensitive resin film to intersect with the first pattern and the first opening. forming a second pattern having apertures; etching away the insulating film exposed at the intersection of the apertures of the first and second patterns; a step of etching away the exposed portion of the conductive resin film, and forming a second conductive layer on the entire surface, and then selectively removing the second conductive layer so as to contact the first conductive layer. and a step of forming a wiring pattern according to the second pattern. (2) Claim 1 characterized in that the same mask as the first pattern formation is used for the first conductive ρ formation.
A method for manufacturing a semiconductor device according to paragraph 1.