Patent Number: 6,309,952

Title: Process for forming high voltage junction termination extension oxide

Abstract: A process for forming a junction termination extension (JTE) oxide havingreduced total oxide charge and SiO.sub.2 --Si interface trap densityparameters uses precursor densified thin oxide layers to improve thequality of subsequently formed thicker oxide layers, and multiple annealsto remove implant damage and set geometry parameters. After formation of afirst dual oxide layer, and a post-oxidation anneal, the oxide ispatterned and JTE regions are implanted. Implant-based near surfacecrystalline damage is annealed out in a non-oxidizing ambient, and JTEdopants are partially driven into adjoining material of the substrate. Athin dense bulk precursor oxide layer is grown on the exposed JTEdopant-implanted surface portions of the substrate, followed by formingthe bulk of the JTE oxide in a steam or wet oxygen atmosphere. Thesubstrate is then annealed in a non-oxidizing ambient, to cause a furtherdrive-in of the JTE dopants. The associated reduction in Qox and Ditimproves high voltage edge stability.

Inventors: Ridley; Rodney S. (Mountaintop, PA), Trost; Jason R. (Drums, PA), Webb; Raymond J. (Mountaintop, PA)


International Classification:

Expiration Date: 10/32013