Zener diode devices and related fabrication methods
View Patent ↗Zener diode structures and related fabrication methods and semiconductor devices are provided. An exemplary semiconductor device includes first and second Zener diode structures. The first Zener diode structure includes a first region, a second region that is adjacent to the first region, and a third region adjacent to the first region and the second region to provide a junction that is configured to influence a first reverse breakdown voltage of a junction between the first region and the second region. The second Zener diode structure includes a fourth region, a fifth region that is adjacent to the fourth region, and a sixth region adjacent to the fourth region and the fifth region to provide a junction configured to influence a second reverse breakdown voltage of a junction between the fourth region and the fifth region, wherein the second reverse breakdown voltage and the first reverse breakdown voltage are different.
1. A semiconductor device comprising:
a semiconductor substrate;
a first Zener diode structure on the semiconductor substrate, the first Zener diode structure including:
a first region having a first conductivity type and a first dopant concentration;
a second region having a second conductivity type and a second dopant concentration, the second region being adjacent to the first region to provide a vertical junction between the first region and the second region, the first region overlying the second region; and
a third region adjacent to the first region and the second region to provide a lateral junction between the third region and one of the first region or the second region, wherein the lateral junction is configured to influence a first reverse breakdown voltage of the vertical junction; and
a second Zener diode structure on the semiconductor substrate, the second Zener diode structure including:
a fourth region having the first conductivity type and the first dopant concentration;
a fifth region having the second conductivity type and the second dopant concentration, the fifth region being adjacent to the fourth region to provide a third junction between the fourth region and the fifth region; and
a sixth region adjacent to the fourth region and the fifth region to provide a fourth junction between the sixth region and one of the fourth region or the fifth region, wherein the fourth junction is configured to influence a second reverse breakdown voltage of the third junction, wherein:
the second reverse breakdown voltage and the first reverse breakdown voltage are different; and
a third reverse breakdown voltage of the lateral junction is greater than the first reverse breakdown voltage of the vertical junction.
2. The semiconductor device of claim 1 , wherein the lateral junction is angled with respect to the vertical junction.
3. The semiconductor device of claim 2 , wherein the lateral junction is substantially orthogonal to the vertical junction.
4. The semiconductor device of claim 1 , wherein the third region has the second conductivity type to provide the lateral junction between the third region and the first region.
5. The semiconductor device of claim 4 , wherein a dopant concentration of the third region is less than the second dopant concentration of the second region.
6. The semiconductor device of claim 4 , wherein the second dopant concentration of the second region is greater than the first dopant concentration of the first region.
7. The semiconductor device of claim 1 , wherein the third region has the first conductivity type to provide the lateral junction between the third region and the second region.
8. The semiconductor device of claim 7 , wherein the first dopant concentration of the first region is greater than the second dopant concentration of the second region.
9. The semiconductor device of claim 7 , wherein a dopant concentration of the third region is greater than the first dopant concentration of the first region.
10. The semiconductor device of claim 7 , wherein:
the first region comprises an anode region;
the second region comprises a cathode region; and
the third region comprises an anode enhancement region.
11. The semiconductor device of claim 1 , wherein the third region laterally circumscribes the first region and the second region.
12. The semiconductor device of claim 1 , wherein the third region and the sixth region have a third dopant concentration.
13. The semiconductor device of claim 1 , wherein a lateral dimension of one of the first region and the second region is different from that lateral dimension of one of the third region and the fourth region.
14. A method of fabricating a semiconductor device structure on a semiconductor substrate, the method comprising:
concurrently forming a first region and a second region in the semiconductor substrate, the first region and the second region having a first conductivity type and a first dopant concentration, the first region having a lateral dimension that is different from that lateral dimension of the second region; and
concurrently forming a third region and a fourth region in the semiconductor substrate, the third region and the fourth region having a second conductivity type and a second dopant concentration, the third region being adjacent to the first region to provide a first junction between the first region and the third region and the fourth region being adjacent to the second region to provide a second junction between the second region and the fourth region, wherein:
a first reverse breakdown voltage of the first junction is different from a second reverse breakdown voltage of the second junction;
a fifth region in the semiconductor substrate adjacent to the first region and the third region provides a third junction between the fifth region and one of the first region or the third region; and
the third junction influences the first reverse breakdown voltage of the first junction.
15. A semiconductor device comprising:
a semiconductor substrate;
a first Zener diode structure on the semiconductor substrate, the first Zener diode structure including:
an anode region having a first conductivity type and a first dopant concentration;
a cathode region having a second conductivity type and a second dopant concentration, the anode region overlying the cathode region and the cathode region being adjacent to the anode region to provide a vertical junction between the anode region and the cathode region; and
an anode enhancement region having the first conductivity type adjacent to the anode region and the cathode region to provide a lateral junction between the anode enhancement region and the cathode region, wherein the lateral junction is configured to influence a first reverse breakdown voltage of the vertical junction; and
a second Zener diode structure on the semiconductor substrate, the second Zener diode structure including:
a fourth region having the first conductivity type and the first dopant concentration;
a fifth region having the second conductivity type and the second dopant concentration, the fifth region being adjacent to the fourth region to provide a third junction between the fourth region and the fifth region; and
a sixth region adjacent to the fourth region and the fifth region to provide a fourth junction between the sixth region and one of the fourth region or the fifth region, wherein the fourth junction is configured to influence a second reverse breakdown voltage of the third junction, wherein:
the second reverse breakdown voltage and the first reverse breakdown voltage are different.
16. A semiconductor device comprising:
a semiconductor substrate;
a first Zener diode structure on the semiconductor substrate, the first Zener diode structure including:
a first region having a first conductivity type and a first dopant concentration;
a second region having a second conductivity type and a second dopant concentration, the second region being adjacent to the first region to provide a lateral junction between the first region and the second region; and
a third region adjacent to the first region and the second region to provide a vertical junction between the third region and one of the first region or the second region, wherein the vertical junction is configured to influence a first reverse breakdown voltage of the lateral junction; and
a second Zener diode structure on the semiconductor substrate, the second Zener diode structure including:
a fourth region having the first conductivity type and the first dopant concentration;
a fifth region having the second conductivity type and the second dopant concentration, the fifth region being adjacent to the fourth region to provide a third junction between the fourth region and the fifth region; and
a sixth region adjacent to the fourth region and the fifth region to provide a fourth junction between the sixth region and one of the fourth region or the fifth region, wherein the fourth junction is configured to influence a second reverse breakdown voltage of the third junction, wherein:
the second reverse breakdown voltage and the first reverse breakdown voltage are different; and
a third reverse breakdown voltage of the vertical junction is greater than the first reverse breakdown voltage of the lateral junction.