3rd International Conference on Modulated Semiconductor Structures

J. Phys. Colloques 48 (1987) C5-605-C5-609
DOI: 10.1051/jphyscol:19875130

HIGH QUALITY SELECTIVE CONTACTS TO n-i-p-i DOPING SUPERLATTICES

G. HASNAIN¹, C.J. CHANG-HASNAIN¹, G.H. DÖHLER², N.M. JOHNSON³, D. MARS⁴, J.N. MILLER⁴ et J. WHINNERY<sup>1

1</sup>  Electrical Engineering Department and Electronics Research Laboratory, University of California, Berkeley, CA 94720, U.S.A.
²  Institut für Technische Physik der Universität Erlangen-Nürnberg, Erwin-Rommel-Strasse 1, D-8520 Erlangen, F.R.G.
³  Xerox Palo Alto Research Center, 3333 Coyote Hill Rd., Palo Alto, CA 94304, U.S.A.
⁴  Hewlett-Packard Laboratories, 3500 Deer Creek Rd., Palo Alto, CA 94304-1317, U.S.A.

Abstract
Using a shadow-mask MBE technique for the fabrication of n-i-p-i doping superlattices with in situ grown-in selective n- and p- type contacts we have made a break-through with respect to the technical problem of selectively contacting the n- and p- layers in highly doped n-i-p-i superlattices. We report a number of investigations which could be performed successfully for the first time due to our new technique. Tunable room temperature electroluminescence with an external quantum efficiency of about 2 % was observed over a photon energy range corresponding to the half band gap of GaAs. In electroabsorption experiments the modulation of optical transmision through a n-i-p-i crystal was observed for the first time. In a n-i-p-i of only 2µm thickness a 22 % transmission change close to the bulk band gap was found. At photon wave lengths of about 1µm the absorption coefficient could be changed by 2 1/2 orders of magnitude by applying bias between -1.5 and +0.5 volts.