Reduction of oxygen impurity at GaN/β-Si3N4/Si interface via SiO2 to Ga2O conversion by exposing of Si surface under Ga flux

Decoupling the Two Roles of Ga Droplets in the Self-Catalyzed Growth of GaAs Nanowires on SiOx/Si(111) Substrates

“…Like in our analysis above, the low sticking of Ga adatoms on the substrate at high T d can be attributed to desorption of Ga and/or Ga 2 O from the SiO x surface. In fact, the onset of Ga loss from the substrate surface at T d ≈ 520 °C is in agreement with what has been reported for Ga 2 O by Kumar et al 36 using in situ residual gas analyzer measurements. Nevertheless, desorption of Ga in parallel to that of Ga 2 O cannot be ruled out.…”

“…In fact, only a very small portion of the deposited Ga atoms remained on the substrate surface at low T a1 (0.01% at 690 °C), whereas this portion increased at higher T a1 (10% at 770 °C). This significant loss of deposited Ga from the SiO x surface can be attributed to desorption of Ga adatoms , and/or Ga 2 O molecules . The latter is the product of the chemical reaction between Ga adatoms and O atoms from the SiO x layer.…”

“…This significant loss of deposited Ga from the SiO x surface can be attributed to desorption of Ga adatoms 34,35 and/or Ga 2 O molecules. 36 The latter is the product of the chemical reaction between Ga adatoms and O atoms from the SiO x layer. The variation of the number density of Ga droplets and of the sticking coefficient of Ga adatoms by several orders of magnitude just by changing T a1 (for the same T d ) manifests that the thermal annealing in step-1 modifies significantly the SiO x surface.…”