JPS61276352A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To protect an element against an electrostatic external force and a radioactive ray by providing a conductive film through an insulating protective film to coat a semiconductor element, and connecting the ground potential of an element. CONSTITUTION:An insulating protective film 27 is formed on a semiconductor element formed as prescribed to form an electrode window 28. A metal film 29 of the same type as wirings is coated by a CVD method or a coating method. The temperature at coating time is 550 deg.C or lower to avoid the formation of an element, and the thickness is of the degree not to disconnect. A window 30 is opened at the film 29, partly superposed with an electrode 32 of the ground potential to form a connector 31. The film 29 is connected with the ground potential in the element with the construction, and an electrostatic external force is particularly shielded to obtain an semiconductor device having no damage nor characteristic deterioration.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method of manufacturing a semiconductor device, which is particularly capable of shielding electrostatic external forces to prevent element destruction and deterioration of element characteristics.

Techniques for preventing soft errors caused by radiation in semiconductor devices, particularly alpha particles in dynamic memory devices, are known, for example, from Japanese Patent Publication No. 59-48552.

FIG. 3 is a process explanatory diagram showing an example of a conventional method for manufacturing a semiconductor device. In this FIG. layer, 15 is an interlayer insulating film, 16 is wiring for electrode extraction, 17
18 indicates an insulating protective film, and 18 indicates an electrode extraction window.

In this conventional manufacturing method, first, as shown in FIG. Placement
ll 6t" are sequentially formed to form a semiconductor element portion.

Thereafter, an insulating protective film 17 is formed to protect the semiconductor element from moisture and mechanical scratches, as shown in FIG. 3(b).
Obtain the configuration shown in Usually, this insulating protective film 17 is made of an oxide film grown in a vapor phase or an insulating film made of polymer resin.

After this, the insulating protective film 17 is processed by the well-known photorin technology, and the electrode extraction window 18 is opened to obtain the structure shown in FIG. 3(c), thereby completing the uniform processing of the semiconductor device. do.

Conventionally, after this, a silicon coating process called a chip coat was added during the assembly process as a measure against radiation such as alpha rays.

(Problems to be Solved by the Invention) However, in the above manufacturing method, the semiconductor insulating film may be destroyed by electrostatic external forces induced during the subsequent package assembly process or handling of the semiconductor device. P-) Electrons etc. are injected into the insulating film,
There were problems with the reliability of the device, such as significant deterioration of device characteristics.

Additionally, there was a problem in that a process called chip coating had to be introduced as a countermeasure against alpha rays.

This invention solves the problems of the above-mentioned prior art.
The present invention provides a method for manufacturing semiconductor devices that solves the problems of electrostatic destruction of elements and deterioration of element characteristics, and the necessity of introducing a silicon coating process called chip coating. .

(Means for Solving the Problems) The present invention introduces a step of forming a conductive film to cover the semiconductor element after forming an insulating protective film on the semiconductor element in a method of manufacturing a semiconductor device. It is.

(Function) According to the present invention, since the above-described steps are introduced into the method of manufacturing a semiconductor device, the insulation on the semiconductor element can be improved. ! l!
When the conductive coating on the membrane is connected to an electrode at ground potential, the induced static electricity is conducted to ground.

(Example) An example of the method for manufacturing a semiconductor device of the present invention will be described below with reference to the drawings. FIGS. 1(a) to 1(c) are process explanatory diagrams of one embodiment, and FIG. 2 is a plan view of a semiconductor device obtained by the present invention.

1(a) to 1(c) and FIG. 2, 21 is a semiconductor substrate, 22 is a P-), 18 is a green film, 23 is a P-to electrode, 24 is a diffusion layer, and 25 is an interlayer. Insulating film, 26 is wiring for electrode extraction, 27 is an insulating protective film, 28 is a window for electrode extraction, 29 is a conductive film, 30 is a conductive film opening window, 31
3 represents an electrical connection between the ground potential of the semiconductor element and the conductive film, and 32 represents an electrode at the ground potential.

First, FIG. 1 (&) shows the configuration of a semiconductor device in which an electrode extraction window 28 is formed in an insulating protective film 27 formed on a semiconductor element, and a conventional wafer process is completed.

In the present invention, a conductive film 29 is then deposited on the entire surface of the semiconductor device as shown in FIG. 1(b). Conductive film 2
9 may be a metal such as Al, Ti, W, Mo, etc., but it is preferable to use the same type of metal as the electrode lead wiring to avoid corrosion due to the battery effect between different metals. The conductive film 29 may be deposited by any method such as vapor deposition, sputtering, CVD, or coating, but CVD and coating methods that do not cause physical effects (damage, etc.) on the device during deposition are preferred. preferable.

Further, the temperature at which the conductive film 29 is deposited is 550° or less to avoid metamorphosis of the semiconductor element. The thickness of the conductive film 29 is not particularly limited, but may be a thickness that does not cause breakage in the steps of the insulating protective film 27.

After the conductive film 29 is deposited on the entire surface of the semiconductor device in this way, it is coated with the well-known IJ method as shown in FIG.
), an opening window 30 of the conductive film 29 is formed. At this time, the conductive coating 29 is partially overlapped with the electrode 32 at the ground potential as shown in FIG.
) and three electrical connections between the ground potential of the semiconductor element and the conductive film 29 as shown in FIG.

When the conductive film 29 covers the entire area of the electrode 32 at ground potential, the ponging property in the subsequent assembly process will be different from that of other electrodes, so in order to prevent this, the conductive film opening window 30 is
In the photolithography process at this time, the electrodes other than the electrode 32 at earth potential are
This electrode portion 32 and the conductive coating 29 in an area several micrometers around it are also etched away at the same time.

In this way, a semiconductor device having a structure in which the conductive film 29 is formed on the semiconductor element and the conductive film 29 is connected to the earth potential electrode within the semiconductor element is obtained.

Further, the conductive film may be grounded from a terminal outside the semiconductor device, and in this case, a step of connecting the conductive film and the external ground terminal may be added after the semiconductor device is formed.

(Effects of the Invention) As explained in detail above, according to the present invention, a conductive film is provided via an insulating protective film to cover a semiconductor element, and this is connected to the earth potential of the element. ,
It is possible to shield electrostatic external forces induced during the packaging process or during the handling of semiconductor devices.

Therefore, it is possible to prevent destruction of the semiconductor element and deterioration of the element characteristics due to this, and there is an advantage that the reliability of the element can be improved.

A device having a %K, 5OI (silicon-on-insulator) structure is susceptible to external electrostatic influences, and this problem can be solved by applying the present invention. Furthermore, since external radiation such as alpha rays can be shielded by the conductive coating, there is an advantage that the conventional chip coating process can be omitted. Sara K,
Although this invention has been explained using all MO8 semiconductor devices as an example, it goes without saying that electrostatic shielding and radiation resistance can be expected when applied to other semiconductor devices.

[Brief explanation of the drawing]

1(a) to 1(c) are process explanatory diagrams of an embodiment of the method for manufacturing a semiconductor device of the present invention, and FIG. 2 is a plan view of a semiconductor device obtained by the method for manufacturing the semiconductor device described above. , FIG. 3(a) to FIG. 3(c) are process explanatory diagrams of a conventional method for manufacturing a semiconductor device. 21-0. Semiconductor substrate, 22... dirt insulating film, 23
... P-) Electrode, 24... Diffusion layer, 25... Interlayer insulating film, 26... Wiring for electrode extraction, 27... Insulating protective film, 28... Window for electrode extraction, 29 . . . conductive film, 30 . . . conductive film opening window, 31 . . . electrical connection portion, 32 . Patent applicant: Oki Electric Industry Co., Ltd. Semiconductor Equipment

Claims (2)

[Claims] (1) (a) a step of forming a semiconductor element on a semiconductor substrate; (b) a step of depositing an insulating protective film on the semiconductor element and forming an opening corresponding to an electrode portion; (c) the above-mentioned step. (d) removing the conductive film on other openings other than the opening corresponding to the ground electrode of the semiconductor device; A method for manufacturing a semiconductor device, comprising the steps of: (2) (a) Step of removing the conductive film from the opening corresponding to the electrode part after depositing the conductive film, and (b) connecting the remaining conductive film to the external ground terminal of the semiconductor device. The method for manufacturing a semiconductor device according to claim 1, comprising the steps of: