Fabrication of high quality silicon related films with band-gap of 1.5 eV by chemical annealing

Abstract Hydrogen radical flux tended to promote crystallization at substrate temperature higher than 200°C accompanying reduction in the hydrogen content. By the addition of Ar ∗ into H, the crystallization was partly prevented with the aid of ion-bombardment. Addition of a small amount of Ge efficiently prevented the crystallization induced by chemical annealing at higher substrate temperature. Consequently, a-SiGe 0.1 :H with a band-gap of 1.67 eV with a defect density less than 6 × 10 15 cm −3 was fabricated by chemical annealing at T s = 250°C. a-SiGe 0.2 :H with a band-gap of ∼ 1.5 eV showing low defect density was successfully made by preventing permeation of hydrogen into Si-network with the aid of Ar ∗ .