Ohmic contacts on sputtered a-Si : H

Abstract

2014 Nous montrons que des contacts ohmiques sont obtenus par pompage d'hydrogène contenu dans les films a-Si: H. Ces contacts ohmiques sont réalisés après diffusion de l'hydrogène dans les films adjaccnts de la structure tels que le « a-Si » à 190 °C ou le « Pd » à température ambiante. Abstract. 2014 We show that ohmic contacts can be obtained by hydrogen depletion in a-Si : H. We obtain these ohmic contacts by diffusion of hydrogen into adjacent films of pure a-Si at 190 °C or Pd at room temperature.

Effect of a hydrogen plasma on various a-Si : Hx structures at low temperatures

“…We report here electrical conductivity measurements in a sandwich cell configuration. We show elsewhere [5] that good ohmic contacts can be achieved by progressively introducing a large amount of localized states in the a-Si :.H gap in the vicinity of its interfaces with other materials, by progressively depleting a sufficient amount of hydrogen. This can be obtained, for instance, by diffusion of hydrogen at 190 °C from a depth of 400 A in the a-Si : H towards adjacent films of pure a-Si or Pd.…”

“…Such low activation energies for the relaxation of the Si matrix were already described from the exodiffusion of hydrogen [4], and from the possibility of fast hydrogen diffusion at low temperature (190 ~C) from a-Si : H to other adjacent solid films (e.g. pure a-Si and Pd) [5].…”

Thickness dependence of hydrogen in a-Si : H films deposited on c-Si

“…Are there significant surface or substrate effects and compositional heterogeneity in 0-1 tim samples ? Preliminary results [7] suggest inhomogeneous distribution of the silicon matrix deformations near the film interfaces with neighbouring films.…”