Accession Number : ADA255569


Title :   Si Atomic Layer Epitaxy Based on Si2H6 and Remote He Plasma Bombardment


Descriptive Note : Technical rept.


Corporate Author : TEXAS UNIV AT AUSTIN DEPT OF ELECTRICAL AND COMPUTER ENGINEERING


Personal Author(s) : Mahajan, A ; Irby, J ; Kinosky, D ; Qian, R ; Thomas, S ; Bancerjee, S ; Tasch, A ; Picraux, Tom


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a255569.pdf


Report Date : 03 Jun 1992


Pagination or Media Count : 3


Abstract : Atomic layer Epitaxy(ALE) of silicon has been demonstrated by using remote helium plasma low energy bombardment to desorb H from a H-passivated Si(100) surface at low temperatures and subsequently chemisorbing disilane on the surface in a self limiting fashion in a Remote Plasma Chemical Vapor Deposition(RPCVD) system in which the substrate is downstream from an r-f noble gas(He or Ar) glow discharge in order to minimize plasma damage. It was found necessary to desorb the H from the Si surface to create adsorption sites for Si bearing species such as Si2H6. Optimal He bombardment parameters were to be 30 W at 100 mTorr He at 400 deg C for 1-3 min. Helium was found to be more effective than Ar bombardment because of the closer match of the He and H masses compared to that between Ar and H. Monte Carlo TRIM simulations of He and Ar bombardment of H-terminated Si surfaces were performed to validate this hypothesis and to predict that approximately 3 surface H atoms are displaced by the incident He atoms, with no Si atom displacement for the energies in the range of 15-60 eV. Alternate Si2H6 dosing and He low energy bombardment cycles (-100-200) were performed to confirm ALE-mode of growth. It was found that the growth per cycle saturates with long Si2H6 dosing at a level which increases with He bombardment time. Silicon, Disilane, Atomic layer epitaxy, He Plasma.


Descriptors :   *LAYERS , *VAPOR DEPOSITION , *ATOMS , *HELIUM , *SILICON , SIMULATION , REPRINTS , TEMPERATURE , VAPORS , DISPLACEMENT , ENERGY , ARGON , GLOW DISCHARGES , BEARINGS , LOW ENERGY , DEPOSITION , SURFACES , TIME , CYCLES , MONTE CARLO METHOD , DESORPTION , SUBSTRATES , EPITAXIAL GROWTH , SITES , ADSORPTION , PARAMETERS , DAMAGE , CHEMICALS


Subject Categories : Physical Chemistry
      Crystallography
      Atomic and Molecular Physics and Spectroscopy
      Plasma Physics and Magnetohydrodynamics


Distribution Statement : APPROVED FOR PUBLIC RELEASE