Gaussian distribution of inhomogeneous Barrier Height in Au-GaP (100) Schottky Barrier diodes

摘要

The current-voltage (I-V) measurements of Au-GaP Schottky barrier diodes (SBD) were carried out in the temperature range of 80-375 K. The values of zero-bias barrier height (?_(B0)) and ideality factor (n) ranged from 0.29 eV and 3.85 (80K) to 0.82 eV and 1.16 (375K), respectively. Such behavior of ?_(B0) and n is attributed to Schottky barrier inhomogeneities by assuming a Gaussian Distribution (GD) of barrier hights (BHs) at Au-GaP interface. The ?_(B0) vs q/(2kT) plot has been drawn to obtain evidence of a Gaussian distribution of the barrier heights,and values of ?_(B0)= 0,97 eV and σ_0= 0.10 V for the mean barrier height and zero-bias standard deviation have been obtained from this plot, respectively. Thus a modified ln (I_0/T~2) - q~2σ~2_0/2k~2T~2vs 1000/T plot has given mean barrier height ?_(B0) and Richardson constant (A*) as 1.95 eV and 0.054 A cm~(-2) K~(-2), respectively. The temperature dependence of the I-V characteristics of the Au-GaP Schottky diode have been successfully explained on the basis of thermionic emission (TE) mechanism with GD of the Schottky barrier heights (SBHs).