JPH01171262A - Semiconductor integrated circuit - Google Patents

Abstract

PURPOSE:To utilize the area of a chip effectively, and to improve the function of a protective diode by forming a P-N junction diode by using a beltlike region shaped, circulating the periphery of the chip. CONSTITUTION:Elements including bipolar-transistors are integrated to a chip 4 in which an N-type semiconductor layer is formed onto a P-type semiconductor substrate 8. A P-N junction diode as a protective element is shaped, circulating the periphery of the chip 4. The diode is formed by an N-type beltlike region 5 partitioned by insulating regions 6 (P<+> isolation regions) and P-type regions 3-1... selectively shaped into the beltlike region 5. Accordingly, since the beltlike region is formed while the P-N junction diode is surrounded on the peripheral section of the chip 4, wirings may be simplified, space can be utilized effectively, the areas of the P-type regions 3-1-3-7 are also taken in large values, and a semiconductor integrated circuit can be given capacity sufficient for a protective diode.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor integrated circuit, and more particularly to a semiconductor integrated circuit including a bipolar transistor and equipped with electrostatic damage and reverse bias protection means.

[Conventional technology]

Conventionally, in this type of semiconductor integrated circuit, a P-N junction diode has been used between the highest potential pad (hereinafter referred to as cc pad) and other pads as a protection element to prevent electrostatic damage. As shown in FIG. 3, the P-N junction diode has a P-type head region 3 selectively provided in an N-type semiconductor layer (for example, 5-5)/J divided by an insulating region (for example, 6-5). Each P-N junction diode was separated by an insulating region.

[Problem that the invention seeks to solve]

The above-mentioned conventional semiconductor integrated circuit has P-N junction diodes each individually partitioned by an insulating region as a protection element, and therefore has drawbacks such as a large chip size and a low protection ability when the circuit is young.

[Means for solving problems]

The semiconductor integrated circuit of the present invention includes a bipolar chip formed by providing a second conductivity type semiconductor layer on a first conductivity type semiconductor substrate.
A strip region of a second conductivity type which is formed by integrating elements including transistors and is provided around the periphery of the chip and partitioned by an insulating region, and a first strip region selectively formed in the strip region.
A P, N junction diode consisting of a conductivity type region is provided as a protection element.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 and FIG. 2 are a schematic plan view and a cross-sectional view, respectively, showing an embodiment of the present invention.

In this embodiment, a bipolar transistor (not shown) is mounted on a chip 4 having an N-type semiconductor layer provided on a P-type semiconductor substrate 8.
It is formed by integrating elements including a
A P-N junction diode consisting of a mold strip region 5 and P-type regions 3-1, . . . selectively formed in the strip region 5 is provided as a protection element.

Vcc pad 1-1 is connected to N+ type region 2, and pads 1-2 to 1-8 are connected to P-type regions 3-1 to 3-7, respectively. The cathodes of each PN junction diode share the N-type semiconductor layer 5 and the N++ buried layer 9. P-type region 3
-1 to 3-87 and N" type region 2 are each vertical NPN
It can be formed in the same process as the pace region and emitter region of the transistor.

Unlike the conventional example, each P-N junction diode is not insulated separately, but a band-shaped region is provided around the chip periphery, so wiring can be simplified, space can be used effectively, and the P-type region The area of 3-1 to 3-7 can also be increased, and they can have sufficient ability as protection diodes.

〔Effect of the invention〕

As explained above, the present invention aims to effectively utilize the chip area and improve the function of the protection diode by providing a P-N junction diode using the band-shaped area provided around the periphery of the chip. There is an effect that it can be done.

[Brief explanation of the drawing]

1 and 2 are a schematic plan view and a sectional view showing an embodiment of the present invention, respectively, and FIG. 3 is a schematic plan view showing a conventional example. 1-1...VCC pad, 1-2 to 1-8...pad, 2...N+ type region 3-1 to 3-7...P type region, 4...chip, 5 ...N-type band-shaped region, 5-1
~5-7...N-type semiconductor layer, 6.6-5.6-8...
- Insulating region, 7-1 to 7-8... Wiring, 8... P-type semiconductor substrate, 9... N++ buried layer, 10... Silicon oxide film.

Claims (1)

[Claims] A chip including a bipolar transistor is integrated into a chip including a semiconductor layer of a second conductivity type on a semiconductor substrate of a first conductivity type, and a transistor including a bipolar transistor is provided around the periphery of the chip and partitioned by an insulating region. P-, which consists of a band-like region of second conductivity type and a region of first conductivity type selectively formed in the band-like region.
A semiconductor integrated circuit comprising an N-junction diode as a protection element.