Motorola Corporation

John P Phipps

Stephen P Robb

Lewis E Terry

Judy L Sutor

Michael D Gadberry

A semiconductor device having an improved protection scheme and a temperature compensated sustaining voltage is provided by integrating a plurality of temperature compensated voltage reference diodes between the drain and the gate of the semiconductor device. The diodes protect the device by clamping the device's sustaining voltage to the total avalanche voltage of the diode. The device will dissipate any excessive energy in the conduction mode rather than in the more stressful avalanche mode. In addition, the plurality of diodes will provide for a temperature compensated sustaining voltage of the semiconductor device. The plurality of diodes are formed back-to-back in polysilicon. The positive temperature coefficient of the avalanching junction of each diode pair is compensated for by the negative temperature coefficient of the forward biased junction.

Method for making semiconductor device having high energy sustaining

Testing of a semiconductor device (10, 30) is facilitated by forming the semiconductor device (10, 30) to have a first portion (17) that is electrically isolated from a second portion (19, 27). Testing is first performed on the first portion (17) of the semiconductor device (10, 30). After the testing is complete, the first portion (17) of the semiconductor device (10, 30) is electrically coupled to the second portion (19, 27) of the semiconductor device (10, 30) .

Method of testing a semiconductor device having a first circuit

Semiconductor device having high energy sustaining capability and a

A semiconductor structure having an edge termination feature wherein at least one guard ring is disposed in a substrate between a main device portion and the edge of the substrate. A dielectric layer is then disposed on the substrate and a plurality of diodes are disposed on the dielectric layer above the at least one guard ring. The at least one guard ring and the diodes are electrically coupled so that the potential of the guard rings may be fixed by the diodes and leakage is greatly reduced.

Edge termination structure

A power transistor having a control electrode which is coupled to a polysilicon JFET transistor is provided. In particular, a power MOSFET device having a polysilicon gate is formed and a JFET transistor is formed in the same polysilicon layer which forms the gate of the power MOSFET. A drain of the JFET forms an input terminal for the power MOSFET and a source of the JFET is coupled to the gate of the power MOSFET. A gate of the JFET is coupled to a gate-drain diode clamp so that when the gate-drain diode clamp is activated a portion of the current which is used to turn on the power MOSFET is channeled to the gate of the JFET and increases the drain-to-source series resistance of the JFET. The resistance of the JFET is low during normal operation and increases only when the gate-drain clamp is activated thus provides a high resistance during avalanche stress protection and a low resistance during normal operation.

Avalanche stress protected semiconductor device having variable input

A power transistor having a control electrode which is coupled to a polysilicon JFET transistor is provided. In particular, a power MOSFET device having a polysilicon gate is formed and a JFET transistor is formed in the same polysilicon layer which forms the gate of the power MOSFET. A drain of the JFET forms an input terminal for the power MOSFET and a source of the JFET is coupled to the gate of the power MOSFET. A gate of the JFET is copupled to a gate-drain diode clamp so that when the gate-drain diode clamp is activated a portion of the current which is used to turn on the power MOSFET is channeled to the gate of the JFET and increases the drain-to-source series resistance of the JFET. The resistance of the JFET is low during normal operation and increases only when the gate-drain clamp is activated thus provides a high resistance during avalanche stress protection and a low resistance during normal operation.

An improved solid state relay and regulator having reduced turn-off time, analog or digital input, and analog or digital output, is obtained by using a depletion JFET as a variable resistance discharge path for a gate of a power MOSFET switching device wherein the gate is charged by a first set of photovoltaic cells optically coupled to but electrically isolated from an LED input. A second set of photovoltaic cells responsive to the same or a separate LED input hold the JFET in an Off state while the MOSFET gate is energized. Variable output and AND logic are obtained.

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Phoenix, AZ, United States of America

John P Phipps