JPS61121348A - Semiconductor device - Google Patents

Abstract

PURPOSE:To improve reliability regarding the damp-proofing of a molding package device by forming a conductor wiring metallic layer on approximately the whole surface of the uppermost layer of a device. CONSTITUTION:A conductor wiring metal 1 is pattern on a substrate 10, and a passivation film 2 is shaped on the whole surface. A nitride film 4 is formed on the whole surface through plasma CVD on a polyimide group resin 3. A contact photo-phosphorus pattern 8 is shaped, and the nitride film 4 in a contact section is removed through plasma dry etching. The polyimide group resin 3 in the contact section and a resist film 5 on the nitride film 4 are removed simultaneously through CF4+O2 group plasma. The passivation film 2 in the contact section and the nitride film 4 on the polyimide group resin 3 are removed at the same time through plasma dry etching. A conductor wiring metal 6 is shaped on the whole surface through sputtering. Lastly, a bonding wire 7 is bonded with a bonding pad area 6a in the conductor wiring metal 6 on the polyimide group resin 3 in a bonding pad shape while the bonding pad area 6a is photolithographic-etched.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application) The present invention relates to a semiconductor device that can significantly improve the reliability of a highly reliable mold package device.

(Prior Art) Currently, mold packages are the mainstream for semiconductor device packages due to cost considerations.

FIG. 2 is a cross-sectional view of a conventional bonding pad section.
10 in FIG. 2 is a substrate. A conductor wiring metal 1 is formed on a substrate 10, and a passivation film 2 is formed thereon.

7 indicates a bonding wire. However, in terms of semiconductor device reliability, compared to ceramic packages, it has fundamental drawbacks (moisture permeability of the resin itself, moisture intrusion from the interface between the resin and leads, etc.). Efforts are being made to compensate for this fundamental drawback and bring the reliability closer to that of ceramic packages. Specifically, (1) Improving the sub-humidity of the passivation film of the semiconductor element itself, (2) Prolonging the reach distance of outside air moisture to the chip by 1 m (hour) due to meandering of the leads, etc. (publication), +31 1f Optimization by examining lipid materials, etc.

(Problems to be Solved by the Invention) However, although various measures have been taken to improve the moisture resistance of mold packaged devices, measures to improve reliability still remain a serious issue.

Paths for the entry of outside air moisture into the molded package device include a path from the bonding wire via the lead frame and a permeation path through the molded package itself.

This invention solves one of the problems that the prior art has.
The present invention provides a semiconductor device that solves the problem of unreliability of molded package devices.

(Means for Solving the Problems) This invention provides conductor wiring photolithography in semiconductor devices.
A passivation film and a polyimide resin layer are formed without forming a bonding pad area in an etching process, and when only the bonding pad is separately formed on the polyimide resin layer, only the conductor wiring metal around the bonding pad is removed. A conductive wiring metal layer is formed almost entirely on the polyimide resin layer.

(Function) According to the present invention, as described above, a bonding pad area is formed on the polyimide resin layer on the surface of the sea urchin to separate the circuit forming area and the bonding pad area, and the bonding pad area is separated from the bonding pad area on the polyimide resin layer. A metal layer for conductor wiring is formed together with the bonding pad.

(Example) An example of the semiconductor device of the present invention will now be described based on the drawings. FIG. 1(al) to FIG. 1(cl) are process diagrams for explaining one embodiment.

In FIG. 1(al) to FIG. 1(cl), the same parts as in FIG. 2 will be described with the same reference numerals.

First, as shown in FIG. 1 (al), after patterning the conductor wiring metal 1 on the substrate 10, a passivation film 2 is formed on the entire surface, and then a polyimide resin 3 is coated on the entire surface and sufficiently cured. .

Next, a film was formed on the polyimide resin 3 by plasma CVD.
), a nitride film 4 is formed over the entire surface at a temperature below aso°C. Furthermore, by applying a resist film 5 on this nitride film 4, conduction with the conductive wiring metal 1 is established using the polyimide resin 3.
A contact photolithographic pattern 8 is formed for drawing upward, and the nitride film 4 at the contact portion is removed by plasma dry etching.

Next, the resist film 5 on the polyimide resin 3 and nitride film 4 in the contact area is removed using CF4+02 plasma.
remove at the same time.

Next, the contact passivation film 2 and the nitride film 4 on the polyimide i-based resin 3 are simultaneously removed by plasma dry etching.

Next, as shown in FIG. 1 fbl, a conductor wiring metal 6 is formed over the entire surface by sputtering. At this time, the conductor wiring metal 6 is made of a material that is electrochemically equivalent to or less noble than the conductor wiring metal 1.

Finally, as shown in Figure 1 (C1), a polyimide 1 m
The bonding wire 7 is bonded to the bonding pad area 6a of the conductor wiring metal 6 on the tray 3, and the main triso etching is performed on the bonding pad area 6a of the bonding pad area 6a. Assume that only the peripheral portion of the bonding wire 70 in the bonding pad area 6a on the polyimide resin 3 is removed.

According to the above configuration, the uppermost layer of the device is almost entirely covered with the conductor wiring metal 6.

In the mold package, the moisture that permeates through the mold 1lfNl itself comes into contact with the conductor wiring metal 6 on the top layer of the device, and selectively reacts (corrosion reaction) with the conductor wiring metal 6. According to
Consumes permeated water.

From this, it is possible to cause a significant delay in the time that moisture reaches the device itself, and it is possible to significantly improve the reliability of the moisture resistance of the mold packaged device.

(Effects of the Invention) As explained in detail above, according to the present invention, a new manufacturing process is adopted in which a polyimide resin layer is formed on the surface of the sea urchin, and a bonding pad area is formed separately from a circuit forming area thereon. Since the conductive wiring metal layer is formed almost entirely on the top layer of the device, the reliability of the moisture resistance of the molded package device can be greatly improved without adding any additional manufacturing process.

[Brief explanation of drawings]

1@(a) to 1rM(e) are process explanatory diagrams for explaining one embodiment of the semiconductor device of the present invention, and FIG. 2 is a sectional view of a conventional bonding pad. 1.6... Conductor wiring metal, 2... Passibasic film, 3... Polyimide resin, 4... Nitride film, 5...
...Resist film, 6a...Bonding pad area,
6b...Circuit formation area, 7...Bonding wire, 8...Contact photolithography pattern. Figure 2 Procedural amendments November-7, 1985

Claims (1)

[Claims] A polyimide resin formed on a substrate via a first conductor wiring metal and a passivation film, and a contact photolithography pattern that exposes the first conductor wiring metal through the polyimide resin and the passivation film. A semiconductor comprising a second conductive wiring metal that is electrically connected to the conductive wiring metal and formed on the polyimide resin separately from a circuit formation area and a bonding pad area, and a bonding wire that is bonded to the bonding pad area. Device.