Patent ID: 6420757
Filing Date: 2002-07-16
Classification: H01L

Abstract:
A cylindrical shaped diode having an anode and a cathode, the diode comprising:a semiconductor substrate of a first conductivity type having first and second surfaces; a pedestal material layer coupled to the semiconductor substrate shaped to form a pedestal having a cylindrical surface; a hollow oxide cylinder having top and bottom surfaces and first and second side cylindrical surfaces and a thickness there between, the first side cylindrical surface coupled to the cylindrical surface of the pedestal, the bottom surface of the hollow oxide cylinder coupled to the first surface of the semiconductor substrate; a first polysilicon gate layer coupled to the cylindrical surface of the pedestal above the top surface of the hollow oxide cylinder and further coupled to the top surface of the hollow oxide cylinder; the substrate having a first diffusion layer of a second conductivity type to form a channel underneath the bottom surface of the hollow oxide cylinder; and the substrate having a second diffusion layer of the first conductivity type within the first diffusion layer of the second conductivity type, the second diffusion layer being adjacent to the cylindrical channel.