Heavily doped polycrystalline 3C-SiC growth on SiO2/Si(100) substrates for resonator applications

3C-SiC is a promising material for the development of microelectromechanical systems (MEMS) applications in harsh environments. This paper presents the LPCVD growth of heavily nitrogen doped polycrystalline 3C-SiC films on Si wafers with 2.0 mu m-thick silicon dioxide (SiO2) films for resonator applications. The growth has been performed via chemical vapor deposition using SiH4 and C2H4 precursor gases with carrier gas of H-2 in a newly developed vertical CVD chamber. NH3 was used as n-type dopant. 3C-SiC films were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), secondary ion mass spectroscopy (SIMS), and room temperature Hall Effect measurements. It was shown that there is no voids at the interface between 3C-SiC and SiO2. Undoped 3C-SiC films show n-type conduction with resisitivity, Hall mobility, and carrier concentration at room temperature of about 0.56 Omega center dot cm, 54 cm(2)/Vs, and 2.0x 10(17) cm(-3), respectively. The heavily nitrogen doped polycrystalline 3C-SiC with the resisitivity of less than 10(-3) Omega center dot cm was obtained by in-situ doping. Polycrystalline SiC resonators have been fabricated preliminarily on these heavily doped SiC films with thickness of about 2 mu m. Resonant frequency of 49.1 KHz was obtained under atmospheric pressure.

Micro-raman investigation of defects in a 4H-SiC homoepilayer

Three types of defects, namely defect I, defect 11, defect 111, in the 4H-SiC homoepilayer were investigated by micro-raman scattering measurement. These defects all originate from a certain core and are composed of (1) a wavy tail region, (11) two long tails, the so called comet and (111) three plaits. It was found that there are 3C-SiC inclusions in the cores of defect 11 and defect III and the shape of inclusion determines the type of defect II or defect III. If the core contains a triangle-shaped inclusion, the defect III would be formed; otherwise, the defect 11 was formed. No inclusion was observed in the core of the defect I. The mechanisms of these defects are discussed.

In situ doping of 3C-SiC grown on (0001) sapphire substrates by LPCVD

The heteroepitaxial growth of n-type and p-type 3C-SiC on (0001) sapphire substrates has been performed with a supply of SiH4+C2H4+H-2 system by introducing ammonia (NH3) and diborane (B2H6) precursors, respectively, into gas mixtures. Intentionally incorporated nitrogen impurity levels were affected by changing the Si/C ratio within the growth reactor. As an acceptor, boron can be added uniformly into the growing 3C-SiC epilayers. Nitrogen-doped 3C-SiC epilayers were n-type conduction, and boron-doped epilayers were p-type and probably heavily compensated.

Indian Country: Travels in the American Southwest

Padget, M. (2004). Indian Country: Travels in the American Southwest. Albuquerque: University of New Mexico Press. RAE2008

The mission as a frontier institution in the Spanish american colonies, by Herbert E. Bolton.

http://www.archive.org/details/missionasfrontie00boltrich

Indian and white in the Northwest : a history of Catholicity in Montana, 1831-1891 / by L.B. Palladino ; with an introduction by John B. Brondel.

http://www.archive.org/details/indianandwhite00palliala

Anthony Ravalli, S.J., forty years a missionary in the Rocky Mountains, memoir / by L.B. Palladino.

http://www.archive.org/details/anthonyravallisj00pallrich

Poor Lo! Early Indian missions. A memorial. By Walter N. Wyeth.

http://www.archive.org/details/poorloearlyindia00wyetiala

In the wake of the war canoe ; a stirring record of forty years' successful labour, peril & adventure amongst the savage Indian tribes of the Pacific coast, and the piratical headhunting Haidas of the Queen Charlotte Islands, B.C., with an introduction by the Lord Bishop of Derry.

http://www.archive.org/details/inwakeofwarcanoe00collrich

Among the Sioux : a story of the Twin Cities and the two Dakotas / by R.J. Creswell ; introduction by David R. Breed.

http://www.archive.org/details/amongsiouxstoryo00cresiala

Isaac McCoy : early Indian missions. Isaac McCoy--Christiana McCoy, a memorial / by Walter N. Wyeth ...

http://www.archive.org/details/isaacmccoycarlyi012072mbp

Missions to the heathen / by L.C. Barnes.

http://www.archive.org/details/missionstoheathe00barnrich

The Moravian missions in Ohio. By Francis C. Huebner.

http://www.archive.org/details/moravianmissions014001mbp

Metlakahtla : a true narrative of the red man / by George T.B. Davis.

http://www.archive.org/details/metlakahtltruena00davirich