| US 7,541,640 B2 | ||
| Vertical field-effect transistor and method of forming the same | ||
| Berinder P. S. Brar, Newbury Park, Calif. (US); and Wonill Ha, Thousand Oaks, Calif. (US) | ||
| Assigned to Flextronics International USA, Inc., San Jose, Calif. (US) | ||
| Filed on Jun. 19, 2007, as Appl. No. 11/765,324. | ||
| Claims priority of provisional application 60/815479, filed on Jun. 21, 2006. | ||
| Prior Publication US 2007/0296028 A1, Dec. 27, 2007 | ||
| Int. Cl. H01L 29/732 (2006.01) | ||
| U.S. Cl. 257—329 [257/476; 257/E29.262; 438/212; 438/268] | 30 Claims |
| 21. A power converter coupled to a source of electrical power and configured to provide a regulated output characteristic,
comprising:
a semiconductor device, including:
a power switch formed as a vertical field-effect transistor, including:
a heavily doped substrate,
a channel layer above said heavily doped substrate,
a heavily doped source/drain layer above said channel layer,
a source/drain contact above said heavily doped source/drain layer,
pillar regions including said source/drain contact, said heavily doped source/drain layer, and portions of said channel layer
to form a vertical cell therebetween,
non-conductive regions in said portions of said channel layer within said pillar regions, and
a gate above said non-conductive regions in said pillar regions, and
a Schottky diode, including:
a contact below said heavily doped substrate within said vertical cell and pillar regions and within a trench through said
heavily doped substrate to said channel layer outside of said vertical cell and said pillar regions, said contact within said
vertical cell and pillar regions providing another source/drain contact for said vertical field-effect transistor, said contact
within said trench providing an anode configured to cooperate with said channel layer that provides a cathode for said Schottky
diode;
a controller configured to control conduction intervals of said power switch to provide said regulated output characteristic;
and
an output filter coupled to said power switch to filter said output characteristic.
|