Quantum-well intermixing process for large blueshifting in an ion-implanted InGaAs/InGaAsP multiple-quantum-well structure using two-step annealing

We describe studies on implantation-enhanced quantum-well intermixing in a lattice-matched InGaAs / InGaAsP multiple-quantum-well p-i-n heterostructure. Samples are implanted with a dose of 5 x 1014 P+ ions /cm2 at a high energy of 1 MeV. The band gaps in the samples are determined from the photoluminescence at room temperature. The Rapid Thermal Annealing (RTA) process is carried out at 675 .deg. C for 9 minutes, and the blue-shift of the band gap is as large as 107 nm. However, the band shift is improved to 140 nm when a novel two-step annealing process is conducted at 675 .deg. C (9 min) and at 875 .deg. C (1 min) in sequence.