Integrated zener diode protection structures and fabrication met

Details Integrated zener diode protection structures and fabrication met Integrated zener diode protection structures and fabrication met

1996-04-12

1997-02-11

Chaudhari, Chandra

Fishing, trapping, and vermin destroying

437150, 148DIG126, 148DIG174, H01L 21266

Patent

active

056020465

ABSTRACT:
In one embodiment, modifications to the polysilicon gate, body, source, and contact masks of a DMOS process add a source-body monocrystalline gate protection diode under the gate pad by implanting an anode region beneath the gate. The anode is connected to the gate through the gate metal in the pad. In addition to the gate-source diode, there is a connection from the drain to the gate through the anode formed by the body region beneath the gate. This embodiment includes a junction terminating field plate. The field plate creates a protection device similar to a zener diode, but exhibits a current/voltage characteristic similar to a thyristor. A significant feature of this embodiment is that the zener breakdown voltage is easily adjusted by a simple modification to the fabrication process. The field plate creates two opposing junctions with the spacing determined by the field plate length. The concentration gradients under the field plate, and hence the breakdown voltage, is controlled by suitable field plate length and other processing conditions. A zener breakdown programmability option is implemented so that the zener breakdown voltage is varied by suitable process selection using only one additional implant, temperature cycle, and photolithographic mask. The zener diode gate protection structure formed using the field plate has a high current per unit power; therefore, a smaller protection structure can be implemented compared to the prior art, because more current is conducted for a given size structure.

REFERENCES:
patent: 4798810 (1989-01-01), Blanchard et al.
patent: 4892836 (1990-01-01), Andreini et al.
patent: 4904614 (1990-02-01), Fisher et al.
patent: 5514608 (1996-05-01), Williams et al.
Robb, et al., "Smartdiscretes.TM., New Products for Automotive Applications", IEEE, pp. 109-113, 1989.
Graaff, et al., "Grain Boundary States and the Characteristics of Lateral Polysilicon Diodes", Solid State Electronics vol. 25, No. 1, pp. 67-71, 1982.

Affiliated with

Also associated with

Rating

Integrated zener diode protection structures and fabrication met does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Integrated zener diode protection structures and fabrication met, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Integrated zener diode protection structures and fabrication met will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-341519