g******i 发帖数: 251 | 1 A intrinsic semiconductor is terminated with H. We need to estimate the change
of electron affinity because of the chemisorption of H, and the way we use is
to mode the surface in terms of the parellel plate capacitor. But we need make
an approximation of surface charge density. What's the order of it? | a***n 发帖数: 578 | 2 ok. let us estimate it. on Si surface. each si atom occupy 15 a^2. if each Si
atom has a hydrogen. each hydrogen will have -0.04 charge. then the charge
density is -0.04/15 a^2.
Considering more carefully, you can calculate the charge on Hydrogen layer by
considering the bond distance of Si-H and the affinite of Si and H. and
moreover the effect of electric field.
that is it.
use
need
【在 g******i 的大作中提到】 : A intrinsic semiconductor is terminated with H. We need to estimate the change : of electron affinity because of the chemisorption of H, and the way we use is : to mode the surface in terms of the parellel plate capacitor. But we need make : an approximation of surface charge density. What's the order of it?
|
|