JPS6222441A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To obtain a semiconductor device having high reliability by treating the back of a semiconductor substrate under the state in which the whole surface of the semiconductor substrate is coated with an insulator. CONSTITUTION:Predetermined wirings 2 and an electrode 3 connected to an external lead are formed onto a semiconductor substrate 1, on the surface thereof an element is shaped, and the whole surface of the substrate is coated with an insulator 4. The back of the semiconductor substrate 1 is treated (treatment such as a thinning to predetermined thickness of the substrate), and washed in a washing tank 5 filled with a washing 6. The back of the semiconductor substrate is washed plural times as required, the semiconductor substrate 1, the back thereof is treated completely, and a window is bored to the electrode 3 section for the insulator 4. The external lead is connected to the electrode 3, thus manufacturing a semiconductor device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a semiconductor device, and particularly to a process for processing the back surface of a semiconductor substrate on which elements are formed.

〔overview〕

In the present invention, in the back surface treatment process of a semiconductor substrate on which elements are formed, the back surface treatment is performed with the entire surface of the semiconductor substrate covered with an insulator, thereby reducing the amount of metal compounds generated on the external lead electrode. This is to prevent the occurrence of such problems and to obtain a highly reliable semiconductor device.

[Conventional technology]

Conventionally, the manufacturing method of a semiconductor device is as shown in FIGS. 2(a) to (e).
As shown in the figure, after wiring 2 is placed on the surface of a semiconductor substrate 1 on which elements are formed, the entire surface is covered with an insulator 4, and a window is made for the electrode 3 for the purpose of connection with an external lead. Then, the backside of the semiconductor substrate is processed.

[Problem that the invention seeks to solve]

In the conventional semiconductor device manufacturing method described above, the semiconductor substrate backside processing step is performed with the electrodes 3 for connection to external leads exposed, so that various problems occur during the backside processing step as shown in FIG. 2 Td). Go through a solvent washing step.

Therefore, the metal forming the electrode 3 chemically reacts with the base in the solvent, and the chloride 7 of the electrode metal is generated. If a resin-encapsulated semiconductor device is manufactured in this state and moisture resistance and reliability tests are performed, the water that has entered the resin will react with the electrode chloride, causing failure due to electrode corrosion and reducing the reliability of the semiconductor device. There was a drawback.

An object of the present invention is to provide a method for manufacturing a semiconductor device that can obtain a highly reliable semiconductor device by eliminating the above-mentioned drawbacks.

[Means for solving problems]

The present invention is characterized in that, in a backside treatment step of a semiconductor substrate on which elements are formed, the backside treatment is performed with the entire surface of the semiconductor substrate covered with an insulator.

[Effect]

In the present invention, since the entire surface of the semiconductor substrate is covered with an insulator, the electrodes connected to the external leads do not come into contact with various solvents during the backside processing process of the semiconductor substrate. does not occur. Therefore, by opening electrode windows in the insulator after this backside treatment, a highly reliable semiconductor device can be obtained.

[Example] Next, an example of the present invention will be described with reference to the drawings.

Figures 1 (al to (e+) are explanatory diagrams showing one embodiment of the present invention, which are schematic cross-sectional views or manufacturing state diagrams of a semiconductor device. First, as shown in Figure 1 (al), elements are shown on the surface. Predetermined wiring 2 and electrodes 3 connected to external leads are formed on the formed semiconductor substrate l.

Next, as shown in Figure tb), the entire surface of the substrate is covered with an insulator 4. Next, as shown in FIG. 1 (C1), the back side of the semiconductor substrate 1 is processed (processing such as thinning the substrate to a predetermined thickness), and the semiconductor substrate 1 is cleaned in a cleaning tank 5 filled with a cleaning liquid 6.

This cleaning is performed multiple times as necessary. Thus, the same figure (
A backside-treated semiconductor substrate 1 shown in d) is obtained. Next, as shown in FIG. 4(e), a window is opened in the electrode 3 portion of the insulator 4. All that is left to do is to connect external leads to this electrode 3 to complete the semiconductor device.

A feature of the present invention is that the back surface treatment is performed in the state shown in FIG. 1(C,), as opposed to the conventional example shown in FIG. 1(d).

(Effects of the Invention) As explained above, in the present invention, the method described above prevents the electrode for connection with the external lead from coming into contact with various solvents during the back surface treatment process of the semiconductor substrate. There is no generation of compounds such as chlorides.For this reason, even if water gets into the resin during moisture resistance reliability testing of resin-encapsulated semiconductor devices, the reaction with this electrode is weak (electrode corrosion takes a long time and there is no risk of failure). This has the effect of making it difficult for this to occur, resulting in a highly reliable semiconductor device.

[Brief explanation of drawings]

FIGS. 1(a) to 1(e) are explanatory diagrams showing one embodiment of the present invention. FIGS. 2(a) to 2(e) are explanatory diagrams showing a conventional example. 1... Semiconductor, substrate, 2... Wiring, 3... Electrode,
4... Insulator, 5... Cleaning tank, 6... Solvent, 7...
...Metal chloride. Patent applicant: NEC Corporation 11. ,,−agent
Patent Attorney Naotaka Ide “5;'ri,ko・n Example explanatory diagram;v)1 En

Claims (1)

[Claims] (1) A method for manufacturing a semiconductor device, characterized in that in a backside treatment step of a semiconductor substrate on which elements are formed, the backside treatment is performed with the entire surface of the semiconductor substrate covered with an insulator.