Naik, Gopalakrishna K and Rao, KSRK and Srinivasanb, T and Muralidharan, R and Mehta, SK (2004) Effect of hydrogen on modulation-doped AlGaAs/InGaAs/GaAs heterostructures: a photoluminescence study. In: Solid State Communications., 132 (12). pp. 805-808.
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The effect of hydrogen on donors and interface defects in silicon modulation doped $Al_xGa_1-_xAs/In_yGa_1-_yAs/GaAs$ heterostructures has been investigated by photoluminescence (PL). Hydrogenation was carried out on two sets of samples, one set consists of high quality pseudomorphic heterostructures and another set having partially lattice relaxed structures prone to the defects. On exposure of high quality pseudomorphic structures to hydrogen plasma above $150^oC_,$ a significant blue shift in the PL peak positions as well as bandwidth narrowing is observed. This indicates, the reduction in two-dimensional electron gas in the $In_yGa_1-_yAs$ quantum well due to hydrogen passivation of silicon donors in the $Al_xGa_1-_xAs$ supply layer. The reactivation of the donors is observed upon annealing the hydrogenated sample for 1 h at $250^oC$ under hydrogen ambient. Another interesting feature is a significant improvement in the PL of lattice-relaxed structures upon hydrogenation of the samples above $250^oC_,$ which is attributed to the hydrogen passivation of interface defects due to the misfit dislocations.
|Item Type:||Journal Article|
|Additional Information:||The copyright of this article belongs to Elsevier.|
|Department/Centre:||Division of Physical & Mathematical Sciences > Physics|
|Date Deposited:||28 Mar 2006|
|Last Modified:||19 Sep 2010 04:24|
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