JPH11288934A - Semiconductor integrated circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shield even oblique light by forming a second metal film for covering an entire semiconductor element on a first metal film, while sandwiching an insulation film. SOLUTION: For example, an MOS-type transistor 2 consists of a gate electrode, a source, and a drain on a semiconductor substrate 1, and metal wiring for electrically connecting them. A first metal film 4 that is connected directly to the semiconductor substrate via a contact hole 3 is provided around the MOS-type transistor 2. Also, a second metal film 6 is provided on the MOS-type transistor 2 via an insulation film 7, and the first metal film 4 and the second metal film 6 are connected by a through hole 5. In this case, to prevent oblique light from entering, the contact hole 3 and a through-hole 5 are arranged so that the surrounding of the MOS-type transistor 2 will not be interrupted. In this manner, by installing a lower layer metal film around the semiconductor element, light is shielded and light leakage is reduced, thus stably operating an element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor integrated circuit, and more particularly to a semiconductor integrated circuit directly mounted on a glass substrate such as a driver IC for driving a liquid crystal or an IC for a power supply.

[0002]

2. Description of the Related Art For example, COG (Chip On Glass)
In the case of the technique of directly mounting a semiconductor integrated circuit on a glass substrate as in s), light penetrates through the liquid crystal panel, which easily causes malfunctions. Has been prevented.

FIG. 3 shows an example of light shielding in a conventional semiconductor integrated circuit. FIG. 3A is a cross-sectional structure diagram, and FIG. 3B is a plan layout diagram. In the figure, a second metal film 6 covering the entire top of the MOS transistor 2 is formed to shield light from above.

[0004]

Even when the entire semiconductor element is covered with an upper metal film, in the case of light from an oblique direction, a gap is formed between the terminal portion of the metal film and the semiconductor substrate, and light enters. Was not preferred.

[0005]

In order to solve the above-mentioned problems, in the present invention, a lower metal film is provided not only on a semiconductor element but also laterally so that light can be shielded from oblique light. did. With the above-described configuration, malfunction of the semiconductor element can be prevented even for oblique light.

[0006]

FIG. 1 shows a first embodiment of the present invention. FIG. 1 (a) is a sectional structural view, and FIG. 1 (b) is a plan layout view. According to the present invention, a MOS transistor 2 comprising a gate electrode, a source, a drain provided on a semiconductor substrate 1 and a metal wiring for electrically connecting them is provided.
A first metal film 4 made of aluminum or the like directly connected to the semiconductor substrate via a contact hole 3 around the MOS transistor and an aluminum or the like provided on the MOS transistor via an insulating film 7 The second metal film 6 has a structure in which the first metal film and the second metal film are connected through the through hole 5. Here, in order to prevent light from entering obliquely, contact holes 3
It is preferable that the through holes 5 are arranged so as not to be interrupted around the semiconductor element as shown in FIG.

Of course, the same effect is obtained even if the positional relationship between the contact hole 3 and the through hole 5 is reversed. The first metal film 4 is effective even if it is not connected to the semiconductor substrate via the contact hole 3. In the case where the metal wiring for electrically connecting the source, drain and gate electrodes of the MOS transistor and the first metal film are formed of the same laminated film, the distance between the contact hole and the metal film is preferably shortened.

FIG. 2 shows a second embodiment of the present invention. In the MOS transistor 2 provided on the semiconductor substrate as in the first embodiment, the gate electrode film 8 made of polycrystalline silicon or the like provided around the MOS transistor.
And a first metal film 4 made of aluminum or the like connected to the gate electrode film 8 via the contact hole 3,
A structure in which a second metal film 6 made of aluminum or the like provided on a MOS transistor via an insulating film 7 and a first metal film and a second metal film are connected through a through hole 5 is provided. This embodiment also has a light shielding effect as in the first embodiment.

[0009]

As described above, the present invention shields light by providing a lower metal film around a semiconductor device.
This has the effect of reducing leakage light and realizing stable operation of the element.

[Brief description of the drawings]

FIGS. 1A and 1B show a first embodiment of a semiconductor integrated circuit according to the present invention. FIG. 1A is a sectional structural view, and FIG. 2B is a plan layout view.

FIG. 2 shows a sectional structural view of a second embodiment of the present invention.

FIGS. 3A and 3B show an example of the prior art, in which FIG. 3A is a sectional structural view, and FIG.

[Explanation of symbols]

 Reference Signs List 1 semiconductor substrate 2 semiconductor element (MOS transistor) 3 contact hole 4 first metal film 5 through-hole gate electrode film 6 second metal film 7 insulating film 8 gate electrode film

Claims (1)

[Claims] In a semiconductor integrated circuit, a first metal film provided around a semiconductor element and a first metal film covering an entirety of the semiconductor element disposed on the first metal film with an insulating film interposed therebetween are provided. 2. A semiconductor integrated circuit having a structure in which a second metal film is connected to a first metal film and a second metal film by through holes provided in the insulating film.