Application of mass separated low energy As+ and P+ ion beams for MIBE technique

Growth by MBE of tertiary or quaternary III-V compound semiconductors including both arsenic and phosphorus, such as GaAsP and InGaAsP, is very difficult as the sticking coefficients of group V elements are less than unity and depend on the surface state of the growing film. A new film growth technique for III-V compound semiconductors is being developed where the sticking coefficients of group V elements can be increased. In this technique, the group III element is supplied as a molecular beam to the substrate heated at the growth temperature. The group V element is supplied as a mass separated, high purity ion beam and implanted at an energy of a few hundred eV. With this technique, homoepitaxial growth of GaAs and InP is studied. Characteristics of the MIBE grown films are discussed and related to the flux ratio. A drastic reduction in the necessary group V element arrival rate is achieved by using a low energy ion beam instead of a molecular beam. (author)