Growth of multiple thin layer structures in the GaAs-AlAs system using a novel VPE reactor

• Published in: Journal of crystal growth Vol. 68; no. 1; pp. 431 - 436
• Main Authors: Leys, M.R., Van Opdorp, C., Viegers, M.P.A., Talen-Van Der Mheen, H.J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.1984
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/0022-0248(84)90445-7

We have designed and built a novel, computer-controlled VPE reactor for the growth of thin layer structures with abrupt composition changes. In this vertical “chimney” reactor, the carrier gas together with components are introduced at the bottom of the reactor tube and passed through the inside of a hollow susceptor. It is used for MOVPE growth in the system GaAs to AlAs. We have grown GaAs layers of thicknesses down to 7 Å in between 50 Å thick layers of Al 0.55Ga 0.45As. Also, we have grown a superlattice type structure containing GaAs and AlAs layers of 35 Å thick. Direct observation of the thicknesses of the layers and of the transition width was obtained by means of Transmission Electron Microscopy. By using lattice imaging, it is demonstrated that the composition change from GaAs to AlAs is achieved in approximately one atomic layer.