Thickness control of molecular beam epitaxy grown layers at the 0.01-0.1 monolayer level
Thickness control of molecular beam epitaxy grown layers at the 0.01-0.1 monolayer level
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DOI：
10.1088/0268-1242/27/8/085007
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发表时间：
2012-08-01
影响因子：
1.9
通讯作者：
Kelly, M. J.
中科院分区：
文献类型：
--
作者：
Dasmahapatra, P.;Sexton, J.;Kelly, M. J.
通过半导体隧道势垒的电子隧穿对势垒层的厚度是指数敏感的，并且在最常见的系统中，GaAs中的AlAs隧道势垒，对于固定的偏置电压，厚度的一个单层变化导致隧穿电流的300%变化。我们使用这种程度的灵敏度，以证明在0.06单层的控制水平可以实现在生长中通过分子束外延，和层厚度的几何变化在整个晶片在0.01单层的水平可以被检测到。
Electron tunnelling through semiconductor tunnel barriers is exponentially sensitive to the thickness of the barrier layer, and in the most common system, the AlAs tunnel barrier in GaAs, a one monolayer variation in thickness results in a 300% variation in the tunnelling current for a fixed bias voltage. We use this degree of sensitivity to demonstrate that the level of control at 0.06 monolayer can be achieved in the growth by molecular beam epitaxy, and the geometrical variation of layer thickness across a wafer at the 0.01 monolayer level can be detected.