Semiconductor device with buried conduction path
View Patent ↗A device includes a semiconductor substrate, emitter and collector regions disposed in the semiconductor substrate, having a first conductivity type, and laterally spaced from one another, and a composite base region disposed in the semiconductor substrate, having a second conductivity type, and including a base contact region, a buried region through which a buried conduction path between the emitter and collector regions is formed during operation, and a base link region electrically connecting the base contact region and the buried region. The base link region has a dopant concentration level higher than the buried region and is disposed laterally between the emitter and collector regions.
1. A device comprising:
a semiconductor substrate;
emitter and collector regions disposed in the semiconductor substrate, having a first conductivity type, and laterally spaced from one another; and
a composite base region disposed in the semiconductor substrate, having a second conductivity type, and comprising a base contact region, a buried region through which a buried conduction path between the emitter and collector regions is formed during operation, and a base link region electrically connecting the base contact region and the buried region;
wherein the base link region has a dopant concentration level higher than the buried region and is disposed laterally between the emitter and collector regions,
wherein the buried conduction path extends across an entire lateral extent of the base link region, and
wherein the base link region has a deeper lower boundary than the emitter and collector regions.
2. The device of claim 1 , wherein the emitter and collector regions are contiguously surrounded by the buried region.
3. The device of claim 1 , wherein the base contact region is disposed laterally between the emitter and collector regions.
4. The device of claim 1 , wherein the semiconductor substrate comprises a buried insulator layer and a semiconductor layer disposed on the insulator layer in which the emitter, collector, and composite base regions are disposed.
5. The device of claim 4 , wherein:
the semiconductor layer is an epitaxial layer; and
the buried region corresponds with a portion of the epitaxial layer not doped to form another region of the device.
6. The device of claim 4 , further comprising:
a deep trench isolation (DTI) region extending through the semiconductor layer to define a lateral periphery of the device; and
a well region having the second conductivity type, disposed between the DTI region and the collector region, and configured to disrupt a parasitic conduction path between the emitter and collector regions along the buried insulator layer.
7. The device of claim 1 , wherein the base link region is configured and positioned relative to the collector region such that the buried conduction path has a partially vertical orientation at the collector region.
8. The device of claim 1 , wherein:
the emitter and collector regions comprise an emitter contact region and a collector contact region; and
the device further comprises a first shallow trench isolation (STI) region disposed between the emitter contact region and the base contact region and a second STI region disposed between the base contact region and the collector contact region.
9. A device comprising:
a semiconductor substrate comprising a substrate, a semiconductor layer supported by the substrate, and a buried insulator layer between the substrate and the epitaxial layer;
emitter and collector regions disposed in the semiconductor layer, having a first conductivity type, and laterally spaced from one another; and
a composite base region having a second conductivity type and comprising a base contact region disposed in the semiconductor layer, a buried portion of the semiconductor layer through which a buried conduction path between the emitter and collector regions is formed during operation, and a base link region disposed in the semiconductor layer and electrically connecting the base contact region and the buried portion of the semiconductor layer;
wherein the base link region has a dopant concentration level higher than the buried portion and is disposed laterally between the emitter and collector regions,
wherein the buried conduction path extends across an entire lateral extent of the base link region, and
wherein the base link region has a deeper lower boundary than the emitter and collector regions.
10. The device of claim 9 , wherein the semiconductor layer is an epitaxial layer.
11. The device of claim 9 , wherein the buried portion of the semiconductor layer contiguously surrounds the emitter and collector regions.
12. The device of claim 1 , wherein the collector region does not laterally overlap the base link region.
13. The device of claim 1 , wherein the buried portion through which the buried conduction path is formed during operation is disposed below and under the base link region.
14. The device of claim 9 , wherein the collector region does not laterally overlap the base link region.
15. The device of claim 9 , wherein the buried portion through which the buried conduction path is formed during operation is disposed below and under the base link region.