GATE STACKS AND OHMIC CONTACTS FOR SIC DEVICES

摘要

SiC substrates are cleaned and provided to a process chamber. In-situ plasma surface treatments are applied to further clean the surface of the substrate. A dielectric interface layer is deposited in-situ to passivate the surface. Metal layers having a low work function are deposited above the dielectric interface layer. The stack is annealed at about 500C in forming gas to form low resistivity ohmic contacts to the SiC substrate. SiC substrates are cleaned and provided to a process chamber. In-situ plasma surface treatments are applied to further clean the surface of the substrate. A silicon oxide dielectric interface layer is deposited in-situ to passivate the surface. Optional plasma surface treatments are applied to further improve the performance of the silicon oxide dielectric interface layer. An aluminum oxide gate dielectric layer is deposited above the silicon oxide dielectric interface layer.

主权项

1. A method comprising:
providing a semiconductor substrate,
wherein the semiconductor substrate comprises silicon carbide; cleaning a surface of the semiconductor substrate,
wherein the cleaning comprises a wet process; placing the semiconductor substrate in a process chamber and applying a plasma surface treatment to the surface of the semiconductor substrate; depositing a dielectric layer on the surface of the semiconductor substrate,
wherein the dielectric layer is deposited in-situ after applying the plasma surface treatment such that the surface of the semiconductor substrate is not exposed to ambient air after the plasma surface treatment and before depositing the dielectric layer, andwherein the dielectric layer comprises an oxide; depositing a metal layer above the dielectric layer; and heating the substrate.