Patent ID: 11869982
Assignee: MONOLITHIC POWER SYSTEMS, INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 4:
5. A method of forming a junction field effect transistor (JFET) comprising:
forming a mesa on a substrate, wherein the mesa includes a first layer with a first conductivity type, wherein the first layer is located over a second layer with a second conductivity type, and wherein the first and second conductivity types are opposite;
after forming the mesa, forming a vertical channel region by implanting channel region dopants in the second layer, wherein the vertical channel region has the first conductivity type and is an only channel region of the JFET; and
after forming the mesa, forming a first base region on a sidewall on a first side of the mesa and a second base region on a sidewall on a second side of the mesa,
wherein the vertical channel region is within the mesa between the first base region and the second base region, and the first and second base regions each has the second conductivity type.