JPS6043662B2 - semiconductor equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrode lead-out structure of a semiconductor device, and is mainly used to prevent abnormal contact alloy from occurring at a contact portion between an element such as a high-resistance diffused resistor and an aluminum wiring in a linear IC or the like. Therefore, the purpose is to increase the electrostatic breakdown strength of each terminal such as the contact portion.

In addition, as a conventional alloy prevention structure, U.S. Patent No. 338
There is one disclosed in the specification of No. 2568.

In linear ICs and the like, electrostatic breakdown strength failures may occur at each terminal, particularly at the contact portion between a bonding pad and a diffused resistor. After investigating the cause of this, we found that such damage tends to occur when the contact is formed in a thin part of the diffusion layer with a depth of 1 μm or less, and that aluminum is likely to occur in the area where the diffusion resistor is formed (or in the silicon substrate). It was found that this is because the contact alloy penetrates into the inside and causes an abnormal contact alloy.

In this case, the aluminum penetration phenomenon is accelerated by the heat of each process such as pellet attachment, bonding pads for external lead wires, and sealing. Furthermore, analysis of the aluminum penetration phenomenon revealed that the phenomenon is caused by the formation of a contact hole for the diffused resistor from the bonding pad (i.e., a contact hole is formed in the insulating film formed on the semiconductor substrate to obtain a contact to the diffused resistor). hole)
It was found that the shorter the distance between the aluminum wiring, the more likely it is to occur.

Therefore, we believe that by increasing the distance between the bonding pad and the contact hole (the length of the line connecting the two at the shortest distance), it is possible to increase the length of the aluminum wiring between them and prevent the above penetration phenomenon. It will be done.

In this case, the pellet size becomes large, which increases the cost and may result in a lack of freedom in pattern design.
Therefore, the contact hole needs to be close enough to the bonding pad to allow the Al of the bonding pad to penetrate. The present invention has been made in consideration of the above-mentioned problems and eliminates the above-mentioned conventional drawbacks, and one embodiment thereof will be described below with reference to the drawings.

The figure shows a plan view of one embodiment of the electrode extraction structure according to the present invention.

In the figure, 1 is the bonding pad, linear ICO) Si
An aluminum layer is formed on the pellet 2 near the scribe area 3 to form a substantially rectangular shape as shown in the figure. 4
is a diffused resistor, which is formed as thin as 1 μm or less by selectively diffusing a predetermined impurity into the pellet 2, as described above.

The distance ' between the contact hole 4a of the diffused resistor 4 and the bonding pad 1 is approximately the same as in the conventional case. Reference numeral 5 denotes an aluminum wiring connecting the bonding pad 1 and the diffused resistor 4, which is detoured into a comb shape (a shape having a part parallel to the side of the bonding pad 1 and a part orthogonal to the part). ing.

Therefore, although the distance between the bonding pad 1 and the contact hole 4a is approximately the same length as in the conventional case, the length of the aluminum wiring 5 is larger than the length '. ing. The width of the aluminum wiring 5 is narrower than the width of the aluminum in the contact portion, so that the permeation phenomenon can be more effectively prevented. In particular, as is clear from the drawings, the wiring layer 5 between the bonding pad 1 and the connection portion (contact hole) 4a has a first wiring layer portion along the side of the bonding pad 1 (along the side of the bonding pad 1). and a second wiring layer portion (a portion disposed orthogonal to the parallel arrangement portion) which is located away from the bonding pad 1, and the first wiring layer portion is arranged parallel to the bonding pad 1. It is formed longer than the second wiring layer portion.

Therefore, even if the distance e between the bonding pad 1 and the contact hole (the length of the line connecting the two at the shortest distance) is short, due to the existence of the first wiring layer portion, the distance from the bonding pad to the semiconductor region is substantially shortened. distance can be made sufficiently large. Therefore, it is possible to reliably prevent the material of the bonding pad from penetrating into the semiconductor region. Further, the structure of the wiring layer 5 can increase the electrostatic breakdown strength without sacrificing freedom in pattern design when the depth of the diffusion layer is as thin as 1 μm or less as described above. Further, as is clear from the drawing, the structure of the wiring layer 5 described above is effective when no other wiring layer exists on the line connecting the bonding pad and the connection part at the shortest distance. It is possible to increase the density of Note that the aluminum wiring 5 is not limited to the comb shape, but can be formed into various shapes by simply making it into a detour shape as described above, thereby increasing its length.

As described above, according to the electrode lead-out structure of a semiconductor device according to the present invention, the aluminum wiring connecting the bonding pad and the element such as the diffused resistor in a linear IC or the like is made long, so that the abnormal contact alloy as in the conventional case is avoided. Therefore, it is possible to effectively prevent poor electrostatic breakdown strength of elements such as the diffused resistor caused by this, and the aluminum wiring is connected to the bonding pad and the contact hole as shown in the drawing. Since the shape is such that no other wiring exists within the predetermined area of the pattern, the distance between the bonding pad and the contact hole can be kept at the same level as before, even though the aluminum wiring has become longer. It has the advantage of being able to be freely designed. The detour wiring of the present invention is effective when the contact hole is provided near the bonding pad.

[Brief explanation of the drawing]

The drawing shows one of the electrode extraction structures of the semiconductor device according to the present invention.
FIG. 3 is a plan view of the embodiment. 1... bonding pad, 2... pellet, 3...
... Scribe region, 4... Diffused resistance, 4a... Contact hole, 5... Aluminum wiring, e... Distance between bonding pad and contact hole.

Claims (1)

[Claims] 1. A semiconductor region formed in a semiconductor substrate, a wiring layer having a connecting portion connected to the region and extending on the substrate, and a wiring layer that is spaced apart from the region on the plane above the substrate and connected to the wiring layer. In a semiconductor device having a bonding pad connected thereto, the wiring layer between the bonding pad and the connection portion includes a first wiring layer portion along the bonding pad and a second wiring layer extending away from the bonding pad in the plane above the base body. consisting of the above first part.
The wiring portion is formed longer than the second wiring layer portion, and there is no wiring layer other than the wiring layer on the line connecting the bonding pad and the connection portion at the shortest distance. semiconductor devices.