ISSN:
1077-3118
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Zn diffusivity, DZn in heavily doped pnpn GaAs structures has been measured after growth and annealing. During growth at 650 °C, DZn∼10−12 cm2/s in the buried p-type layer is found to be (approximately-greater-than)104×DZn in the top p-type layer. During annealing at 800 °C, DZn≈5×10−14 cm2/s in the buried layer remains orders of magnitude larger than DZn in the top layer. The measurements provide clear experimental evidence that (1) a large flux of Ga interstitials, IGa, is injected from the surface during the growth of n-type layers, (2) the IGa are trapped in the buried p-type layer by the electric field of the pn junctions, and are thus positively charged, (3) the resulting large concentration of IGa in the buried layer accounts for the enhanced DZn via a kick-out mechanism, and (4) the mobile Zn interstitial is positively charged. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.114507
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