T. Kimura et al., ELECTROCHEMICAL ER DOPING OF POROUS SILICON AND ITS ROOM-TEMPERATURE LUMINESCENCE AT SIMILAR-TO-1.54 MU-M, Applied physics letters, 65(8), 1994, pp. 983-985
We present a new electro-chemical method for incorporating high concen
tration Er ions deep into porous silicon layers and its intense photol
uminescence at approximately 1.54 mum at room temperature. Porous sili
con layers prepared by anodic etching of p-type silicon substrates in
HF/H2O are immersed in ErCl3/ethanol solution. Then the negative bias
relative to a counter platinum electrode is applied to the samples. Er
3+ ions are drawn into fine pores of the porous silicon layers by the
electric field. After thermal annealing at approximately 1300-degrees-
C in an O2/Ar atmosphere, the samples show sharp and intense Er3+-rela
ted photoluminescence at approximately 1.54 mum at room temperature up
on excitation with an Ar ion laser.