Magnetotransport measurements on a damaged surface of $p$-type InAs and the annealing effect

Low-temperature magnetotransport measurements have been performed to study the spatial distribution of conduction electrons near a (111)B surface of $p$-type InAs damaged during a $\mathrm{Si}{\mathrm{O}}_2$-sputtering process. The results obtained for both the in-plane and perpendicular magnetic field orientations are well explained by a two-layer model. The electron density of a three-dimensional electron layer, having submicron thickness, decreases rapidly with an increase in annealing temperature and the conduction is eliminated after annealing above $125°\mathrm{C}$. On the other hand, the conduction of a two-dimensional electron layer at the surface remains after annealing.

Figure 1

Diagonal resistivity ${\rho }_{xx}$ vs magnetic field $B$ at $T=0.34\mathrm{K}$. (a) Data in in-plane magnetic field $B_{\Vert }$ and perpendicular magnetic field $B_{\perp }$. (b) Oscillation component of ${\rho }_{xx}$ as a function of the inverse of $B_{\Vert }$. The period is obtained to be $\Delta (1∕B)=0.0589{\mathrm{T}}^{-1}$.

Figure 2

Diagonal resistivity ${\rho }_{xx}$ and Hall ${\rho }_{xy}$ resistivity in perpendicular magnetic field. The solid curves are fits to the experimental data (see text). The dashed line represents $d{\rho }_{xy}∕d{B}_{\perp }$ in the limit of $B_{\perp }\to 0$.

Figure 3

Zero-field conductivity vs annealing temperature.

Figure 4

(a) Oscillation component of ${\rho }_{xx}$ in an in-plane magnetic field for various annealing temperatures $T_a$. Traces are vertically offset by 0.2 for clarity. (b) Volume density $N_{3\mathrm{D}}$ as a function of $T_a$.

Figure 5

Diagonal resistivity ${\rho }_{xx}$ and Hall ${\rho }_{xy}$ resistivity in a perpendicular magnetic field for various annealing temperatures.

Figure 6

Areal densities and mobilities of 2D and 3D layers as functions of $T_a$.

Figure 7

Effective thickness of the 3D electron layer $d_{3\mathrm{D}}=n_{3\mathrm{D}}∕N_{3\mathrm{D}}$.