Comparison of two surface preparations used in the homoepitaxial growth of silicon films by plasma enhanced chemical vapor deposition

Abstract

Articles you may be interested inThe use of optical microscopy to examine crystallite nucleation and growth in thermally annealed plasma enhanced chemical vapor deposition and hot wire chemical vapor deposition a-Si:H films Microstructure and initial growth characteristics of nanocrystalline silicon films fabricated by very high frequency plasma enhanced chemical vapor deposition with highly H 2 dilution of SiH 4

Final report on LDRD project : single-photon-sensitive imaging detector arrays at 1600 nm.

“…All germanium deposited in this work was found to be polycrystalline when using HF dips followed by directly depositing germanium, which included an initial warm-up step of several minutes in the presence of a 3000W, 10 mtorr (or 1 mtorr) argon plasma followed by introducing 50 µtorr of germane to initiate the Ge deposition once the substrate reached it's steady-state temperature of 460°C. This is consistent with previous reports of plasma assisted epitaxial growth, which typically required an in-situ surface preparation step like a hydrogen plasma clean [15]. Typical plasma cleans rely on hydrogen to assist the formation of volatile silicon oxide and steam from the surface [16].…”

“…It is well known that silicon surfaces can be prepared with relatively low oxygen free hydrogen terminated surfaces through use of an ex-situ HF dips, which is sufficient for thermal CVD systems to grow relatively defect free epitaxy although oxygen and carbon are always found at the substrate growth interface using HF dips only. On the other hand, standard HF dips are not usually sufficiently stable to allow epitaxial growth in plasma systems despite the much lower peak temperatures [15]. All germanium deposited in this work was found to be polycrystalline when using HF dips followed by directly depositing germanium, which included an initial warm-up step of several minutes in the presence of a 3000W, 10 mtorr (or 1 mtorr) argon plasma followed by introducing 50 µtorr of germane to initiate the Ge deposition once the substrate reached it's steady-state temperature of 460°C.…”

“…The oxide and nitride were deposited by high density plasma chemical vapor deposition. The germanium was then implanted with a 160 keV, 4x10 15 cm -2 phosphorus implant using a 7 degree tilt and 22 degree rotation. After implant the wafer was cleaved into smaller samples some of which were annealed at temperatures of 600˚C, 700˚C or 800˚C for either 3 or 10 hours in forming gas (20% H 2 in N 2 ) or nitrogen ambients.…”