Schottky device and method of forming
View Patent ↗A conductive layer includes a first portion that forms a Schottky region with an underlying first region having a first conductivity type. A second region of a second conductivity type underlies the first region, where the second conductivity type is opposite the first conductivity type. A third region of the first conductivity type immediately underlies the second region and is electrically coupled to a cathode of the device.
1. A device comprising:
a first terminal connected to a conductive layer, a first portion of the conductive layer being a Schottky contact;
a first region of a first conductivity type underlying the Schottky contact, a first portion of the first region immediately underlying the Schottky contact;
a second region of a second conductivity type underlying the first region, a first portion of the second region immediately underlying the first portion of the first region, the second conductivity type being opposite the first conductivity type;
a third region of the first conductivity type underlying the second region, a first portion of the third region immediately underlying the second region;
a second terminal overlying the first region and electrically connected to the first region and to the third region; and
a fourth region of the second conductivity type adjacent to the first region in a lateral direction, the fourth region electrically connected to the first terminal, a first portion of the fourth region immediately adjacent in a lateral direction to the second region, wherein the second region is electrically connected to the conductive layer through a tie-portion of the fourth region, and the tie-portion of the fourth region comprises a higher dopant concentration than other portions of the fourth region.
2. The device of claim 1 wherein a second portion of the fourth region immediately underlies a second portion of the conductive layer.
3. The device of claim 2 , wherein the second portion of the conductive layer is immediately adjacent in a lateral direction to the first portion of the conductive layer.
4. The device of claim 3 , wherein a third portion of the fourth region is immediately adjacent to the first region, and has a higher dopant concentration of the second conductivity type than the first portion of the fourth region.
5. The device of claim 1 , wherein the fourth region does not immediately underlie the conductive layer.
6. The device of claim 1 , wherein a second portion of the fourth region overlies the first portion of the fourth region, wherein the second portion of the fourth region comprises a higher dopant concentration than the first portion of the fourth region, and the tie-portion of the fourth region is part of the second portion of the fourth region that is immediately adjacent to the conductive layer.
7. The device of claim 6 , wherein the first portion of the fourth region is physically separated from the tie-portion of the fourth region by the second portion of the fourth region.
8. The device of claim 1 , wherein the third region is electrically connected to the first region.
9. The device of claim 8 , wherein the third region is electrically connected to the first region through a conductive path at least as conductive as the third region.
10. The device of claim 1 , wherein
the first region comprises a plurality of first interleave structures; and
the fourth region comprises a plurality of second interleave structures interleaved with the plurality first interleave structures.
11. The device of claim 1 , wherein the first region and the second region form a first planar interface facing a first direction and the first region and the fourth region form a second planar interface facing a second direction, the first direction and the second direction being substantially orthogonal.
12. The device of claim 11 , wherein the first region and the fourth region form a third planar interface facing a third direction, the third direction and the first direction being substantially orthogonal and the third direction and second direction being substantially orthogonal.
13. The device of claim 1 , wherein the conductive layer is a silicide.
14. The device of claim 1 , wherein the first terminal is an anode of the Schottky contact and the second terminal is a cathode of the Schottky contact.
15. The device of claim 1 , wherein the first terminal is a cathode of the Schottky contact and the second terminal is an anode of the Schottky contact.
16. A device comprising:
a first terminal connected to a conductive layer, a first portion of the conductive layer being a Schottky contact;
a first region of a first conductivity type underlying the Schottky contact, a first portion of the first region immediately underlying the Schottky contact;
a second region of a second conductivity type immediately underlying the first portion of the first region, the second conductivity type being opposite the first conductivity type;
a third region of the first conductivity type immediately underlying the second region;
a second terminal overlying the first region and electrically connected to the first region and to the third region; and
a fourth region of the second conductivity type adjacent to the first region in a lateral direction, the fourth region electrically connected to the first terminal, a first portion of the fourth region immediately adjacent in a lateral direction to the second region, wherein the second region is electrically connected to the conductive layer through a tie-portion of the fourth region, and the tie-portion of the fourth region comprises a higher dopant concentration than other portions of the fourth region.