Power device integration on a common substrate

1. A semiconductor structure comprising at least one bipolar junction transistor (BJT) power device, the semiconductor structure comprising:

an insulating layer formed on the substrate;

an active region formed on at least a portion of the insulating layer;

a collector extension region having a first conductivity type formed in the active region proximate an upper surface of the active region;

a collector region having the first conductivity type formed in at least a portion of the collector extension region proximate an upper surface of the collector extension region, the collector region having a higher doping concentration compared to the collector extension region;

a collector terminal formed on an upper surface of the semiconductor structure and electrically connecting with the collector region;

a buried well having a second conductivity type formed in the active region, the buried well being configured, in conjunction with the active region, to form a clamping diode operative to position a breakdown avalanche region between the buried well and the collector terminal, a breakdown voltage of the bipolar junction transistor being a function of one or more characteristics of the buried well;

a base region having the second conductivity type formed in the active region on at least a portion of the buried well and extending laterally to the collector extension region;

an emitter region having the first conductivity type formed in an upper surface of the base region;

an emitter terminal formed on the upper surface of the semiconductor structure, the emitter terminal being electrically connected with the emitter region; and

a base structure formed on the upper surface of the semiconductor structure above a junction between the base region and the collector extension region, the base structure being isolated from a top surface of the active region and electrically connected with the buried well and a base terminal.

2. The semiconductor structure of claim 1 , wherein the emitter terminal is formed as a finger structure, and an electrical connection between the buried well and the base structure is formed as a lateral extension of a conductive layer contacting the buried well and the base region, the conductive layer overlapping onto the base structure and being electrically connected therewith, the connection interrupting the emitter terminal at prescribed intervals along the finger structure.

3. The semiconductor structure of claim 2 , wherein the conductive layer comprises a conductive lining on a wall of a trench formed in the active region.

4. The semiconductor structure of claim 3 , further comprising a base contact formed at least in part within the trench and in electrical contact with the conductive layer.

5. The semiconductor structure of claim 2 , wherein the base structure is a polycide structure comprising a top silicide layer in contact with the conductive layer.

6. The semiconductor structure of claim 1 , wherein the emitter terminal is formed as a finger structure, and an electrical connection between the buried well and the base structure includes:

a lateral extension of a conductive layer contacting the buried well and the base region, the conductive layer overlapping at least in part the base region and spaced from the base structure; and

a contact having a first portion in contact with an upper surface of base structure and a second portion in contact with an upper surface of the conductive layer, wherein the connection interrupts the emitter terminal at prescribed intervals along the finger structure.

7. The semiconductor structure of claim 6 , wherein the conductive layer at least partially overlaps the base structure and is spaced from the upper surface of the base structure.

8. The semiconductor structure of claim 6 , wherein the conductive layer comprises a conductive lining on a wall of a trench formed in the active region.

9. The semiconductor structure of claim 8 , further comprising a base contact formed at least in part within the trench and in electrical contact with the conductive layer.

10. The semiconductor structure of claim 6 , wherein the base structure is a polycide structure comprising a top silicide layer in contact with the conductive layer.

11. The semiconductor structure of claim 1 , wherein the base structure is operable as a gate controlling current flow from the emitter region to the collector region through a MOS channel.

12. The semiconductor structure of claim 1 , wherein the buried well is formed proximate an interface between the insulating layer and the active region.

13. The semiconductor structure of claim 1 , wherein the at least one BJT power device comprises a plurality of said at least one BJT power devices formed therein and organized in a macro-cell, and the semiconductor structure comprises a plurality of said macro-cells connected together to operate as a single BJT power device.

14. The semiconductor structure of claim 1 , wherein the at least one BJT power device comprises a plurality of like BJT power devices formed therein and connected together through a bus structure to operate as a single BJT power device, wherein the semiconductor structure is part of a chip-scale assembly, the chip-scale assembly comprising a redistribution layer coupling the bus structure to base, collector and emitter external contacts.

15. The semiconductor structure of claim 1 , further comprising control circuitry integrated with the at least one BJT power device on a common substrate, the control circuitry being configured to selectively control operation of the at least one BJT power device.

16. The semiconductor structure of claim 1 , further comprising a shielding structure formed proximate the upper surface of the active region between the base structure and the collector region, the shielding structure comprising a field plate configured to control an electric field distribution along a top oxide interface away from an edge of the base structure nearest the collector terminal.