Ricardo Cotrin Teixeira

Deposition of sacrificial silicon oxide layers by electron cyclotron resonance plasma

Electron cyclotron resonance plasmas with SiH4∕O2∕Ar mixtures were used for deposition of thin films of silicon oxide, to be employed as sacrificial layers in microelectromechanical system (MEMS) fabrication. The grown films were characterized by Fourier transform infrared and ellipsometry. Optical emission spectroscopy and Langmuir probe were used for plasma characterization. It has been shown that OH molecules generated in the plasma play an important role in formation of films suitable as sacrificial layers for MEMS fabrication. Extremely high etch rates of grown oxide films (up to 10μm∕min) were obtained, allowing fabrication of high quality poly-Si suspended structures.Electron cyclotron resonance plasmas with SiH4∕O2∕Ar mixtures were used for deposition of thin films of silicon oxide, to be employed as sacrificial layers in microelectromechanical system (MEMS) fabrication. The grown films were characterized by Fourier transform infrared and ellipsometry. Optical emission spectroscopy and Langmuir probe were used for plasma characterization. It has been shown that OH molecules generated in the plasma play an important role in formation of films suitable as sacrificial layers for MEMS fabrication. Extremely high etch rates of grown oxide films (up to 10μm∕min) were obtained, allowing fabrication of high quality poly-Si suspended structures.

Morphological study of polycrystalline SiGe alloy deposited by vertical LPCVD

As device dimensions shrink to the deep-submicron scale, new challenges arises from the very small scale used and even poly crystalline silicon (poly-Si) presents problems as gate electrode. The use of SiGe as gate material can present many advantages over the poly-Si, as it leads to a lower boron penetration and gate depletion. In this paper authors present some morphological studies of polycrystalline SiGe thin films deposited in a vertical LPCVD (Low Pressure Chemical Vapor Deposition) reactor for using as MOS (Metal Oxide Semiconductor) gate electrode.