Protection device and related fabrication methods
View Patent ↗Protection device structures and related fabrication methods are provided. An exemplary semiconductor protection device includes a base region of semiconductor material having a first conductivity type, an emitter region within the base region having the opposite conductivity type, and a collector region of semiconductor material having the second conductivity type, wherein at least a portion of the base region resides between the emitter region and the collector region. A depth of the collector region is greater than a depth of the emitter region and less than or equal to a depth of the base region such that a distance between a lateral boundary of the emitter region and a proximal lateral boundary of the collector region is greater than zero and the collector region does not overlap or otherwise underlie the emitter region.
1. A semiconductor device comprising:
a first region of semiconductor material having a first conductivity type and a first dopant concentration;
a base well region within the first region, the base well region having the first conductivity type and a second dopant concentration greater than the first dopant concentration of the first region;
a base contact region within the base well region, the base contact region having the first conductivity type and a third dopant concentration greater than the first dopant concentration;
an emitter region of semiconductor material within the base well region, the emitter region having a second conductivity type opposite the first conductivity type; and
a collector region of semiconductor material having the second conductivity type, wherein:
at least a portion of the first region resides between the emitter region and the collector region;
a depth of the collector region is greater than a depth of the emitter region;
a depth of a second portion of the first region underlying the emitter region is greater than or equal to the depth of the collector region;
at least a portion of the base well region resides between the emitter region and the collector region; and
the depth of the collector region is greater than a depth of the base well region.
2. A semiconductor device comprising:
a first region of semiconductor material having a first conductivity type and a first dopant concentration;
a base well region within the first region, the base well region having the first conductivity type and a second dopant concentration greater than the first dopant concentration of the first region;
a base contact region within the base well region, the base contact region having the first conductivity type and a third dopant concentration greater than the first dopant concentration;
an emitter region of semiconductor material within the base well region, the emitter region having a second conductivity type opposite the first conductivity type; and
a collector region of semiconductor material having the second conductivity type, wherein:
at least a portion of the first region resides between the emitter region and the collector region;
a depth of the collector region is greater than a depth of the emitter region;
a depth of a second portion of the first region underlying the emitter region is greater than or equal to the depth of the collector region; and
the collector region comprises:
a well region of semiconductor material having the second conductivity type and a first dopant concentration; and
a buried region of semiconductor material underlying the well region, the buried region having the second conductivity type and a second dopant concentration greater than or equal to the first dopant concentration.
3. A semiconductor device comprising:
a first region of semiconductor material having a first conductivity type;
an emitter region of semiconductor material having a second conductivity type opposite the first conductivity type;
a collector region of semiconductor material having the second conductivity type; and
a base well region within the first region, the base well region having the emitter region formed therein, the base well region having the first conductivity type and a first dopant concentration greater than a second dopant concentration of the first region by a factor of at least 10, wherein:
at least a portion of the first region resides between the emitter region and the collector region;
a depth of the collector region is greater than a depth of the emitter region;
a depth of a second portion of the first region underlying the emitter region is greater than or equal to the depth of the collector region;
a distance between a lateral boundary of the base well region and a proximal lateral boundary of the collector region is greater than zero; and
the portion of the first region resides between the collector region and the base well region.
4. The semiconductor device of claim 1 , wherein:
the first region and the emitter region are coupled to a first terminal; and
the collector region is coupled to a second terminal.
5. The semiconductor device of claim 1 , wherein a distance between a lateral boundary of the emitter region and a proximal lateral boundary of the collector region is greater than zero.
6. The semiconductor device of claim 1 , wherein the collector region does not extend laterally underneath the emitter region.
7. The semiconductor device of claim 1 , wherein the collector region contacts an underlying layer of dielectric material.
8. The semiconductor device of claim 7 , wherein the second portion abuts the underlying layer of dielectric material.
9. The semiconductor device of claim 1 , further comprising:
an isolation region within the first region, wherein:
the isolation region resides laterally between the base contact region and the emitter region; and
the base contact region and the emitter region are electrically connected.
10. The semiconductor device of claim 1 , further comprising:
a first interface;
a second interface; and
functional circuitry coupled between the first interface and the second interface, wherein:
the base contact region and the emitter region are coupled to the first interface; and
the collector region is coupled to the second interface.
11. The semiconductor device of claim 1 , further comprising an isolation region within the base well region, wherein:
the isolation region resides laterally between the base contact region and the emitter region; and
the base contact region and the emitter region are electrically connected.
12. The semiconductor device of claim 2 , wherein the buried region does not extend laterally underneath the emitter region.
13. The semiconductor device of claim 2 , wherein lateral boundaries of the well region are substantially aligned with lateral boundaries of the buried region.
14. The semiconductor device of claim 1 , further comprising:
a second region of semiconductor material having the first conductivity type; and
a second emitter region of semiconductor material having the second conductivity type, wherein:
a third portion of the second region resides between the second emitter region and the collector region;
the depth of the collector region is greater than a depth of the second emitter region; and
a depth of the second region is greater than or equal to the depth of the collector region.
15. The semiconductor device of claim 14 , wherein:
the first region, the emitter region, the second region, and the second emitter region are coupled to a first terminal; and
the collector region is coupled to a second terminal.
16. The semiconductor device of claim 14 , further comprising:
a third emitter region of semiconductor material having the second conductivity type; and
a second collector region of semiconductor material having the second conductivity type, wherein:
a fourth portion of the second region resides between the third emitter region and the second collector region;
a depth of the second collector region is greater than a depth of the third emitter region; and
the depth of the second region is greater than or equal to a depth of the second collector region.
17. The semiconductor device of claim 2 , wherein the base contact region and the emitter region are electrically connected.
18. The semiconductor device of claim 17 , further comprising:
a first interface;
a second interface; and
functional circuitry coupled between the first interface and the second interface, wherein:
the base contact region and the emitter region are coupled to the first interface; and
the collector region is coupled to the second interface.
19. The semiconductor device of claim 2 , wherein:
the first region and the emitter region are coupled to a first terminal; and
the collector region is coupled to a second terminal.
20. The semiconductor device of claim 2 , wherein a distance between a lateral boundary of the emitter region and a proximal lateral boundary of the collector region is greater than zero.