Surface modification of semiconductor by simultaneous thermal oxidation

Abstract

Integration of high-quality functional thin layer of oxides on semiconductor, in particular wide-bandgap silicon carbide, is of extreme importance in order to realize near future generation of metal-oxide-semiconductor (MOS)-based devices for high-power, high-temperature, and/or high-radiation applications. Although nitrided SiO2 on SiC produced acceptable results, limitations and issues have been reported. Therefore, evolution and justification of changing this type of oxide to high dielectric constant oxide (high-κ) on SiC are being reviewed. This chapter presents the current understanding of simultaneous thermal oxidation and nitridation of sputtered Zr-semiconductor interfaces as the most promising technique for achieving device-quality interfaces required for commercial applications. It is mainly focused on the technological methods of producing oxidized/nitrided Zr on SiC. An exceptional section is devoted to the recent developments of nitrided high-κ gate dielectrics on SiC. It starts with a detailed discussion of high-κ gate dielectric characteristics and the current knowledge of simultaneously oxidized and nitrided Zr film as high-κ dielectric on SiC. Via this technique, the role of N2O gas ambient on oxidizing and nitriding Zr film on SiC, coupling with physical and electric characteristics of oxidized/nitrided Zr film on SiC, is discussed. A growth mechanism of simultaneous thermal oxidation and nitridation of Zr film on SiC is subsequently presented. Finally, the properties of oxidized/nitrided Zr thin films based on Si and SiC substrates are compared.