Ion implantation of isoelectronic impurities into InP

Abstract

Ion-implanted InP with several kinds of isoelectronic impurities (B +, N +, P +, As +, Sb + and Bi +) was characterized by photoluminescence (PL) and Raman scattering spectroscopies. The ion concentration was varied between 1 × 10 15 and 1 × 10 20 cm −3. Remarkably broad emissions extending far above the band gap of InP were observed when B + or N + was singly implanted to a concentration of 1 × 10 20 cm −3. They appeared more intensively when InP was ion-implanted with B + as well as with N + to respective concentrations greater than 1 × 10 19 cm −3. These features explicitly demonstrate that a new material was produced by introduction of the same amount of group, III and V elements, suggesting that a mixed compound semiconductor between B, N, In and P, i.e., (BN) x (InP) 1− x is fabricated. The formation of new materials was also shown by Raman scattering measurements. It is indicated that high dose ion implantation of isoelectronic elements of small mass is promising method to produce mixed crystal semiconductors. For As +, Sb + or Bi + ion-implanted InP, a distinct PL emission was commonly observed below bound exciton emissions for concentrations around 1 × 10 16 cm −3. These are, to our knowledge, the first-reported radiative recombination centers attributed of these isoelectronic impurities. Bi was found to form a sharp PL emission below bound exciton emissions, suggesting that implanted Bi becomes an efficient recombination center.