Growth and reliability of thick gate oxide in U-trench for power MOSFETs

Author

Wu, C.-T. ; Ridley, R.S., Sr. ; Dolny, G. ; Grebs, T. ; Knoedler, C. ; Suliman, S. ; Venkataraman, B. ; Awadelkarim, O. ; Ruzyllo, J.

Author_Institution

Pennsylvania State Univ., University Park, PA, USA

fYear

2002

fDate

2002

Firstpage

149

Lastpage

152

Abstract

Growth kinetics and reliability of thick gate oxides grown into 2 μm deep trenches is investigated. The oxide thickness nonuniformities are observed at the bottom of the trench. It is postulated that thinning of the oxide at the bottom of the trench is a result of an insufficient supply of oxidizing species which nonuniformities are enhanced by 2D oxidation in the corners. The effect of 2D oxidation is more pronounced in narrow trenches. The reliability of trench oxides was found to be dependent on the oxidation temperature, trench geometry, and substrate´s conductivity type. No effect of temperature of oxidation and trench geometry on interface trap density was observed.

Keywords

MOS capacitors; oxidation; power MOSFET; semiconductor device reliability; 2 micron; 2D oxidation; U-trench; growth kinetics; oxidation temperature; oxide thickness nonuniformities; power MOSFETs; reliability; substrate conductivity type; thick gate oxide; trench geometry; Breakdown voltage; Contacts; Etching; Geometry; MOS capacitors; MOSFET circuits; Oxidation; Power MOSFET; Scanning electron microscopy; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Power Semiconductor Devices and ICs, 2002. Proceedings of the 14th International Symposium on

Print_ISBN

0-7803-7318-9

Type

conf

DOI

10.1109/ISPSD.2002.1016193

Filename

1016193