THERMAL-TREATMENT OF THE MIS AND INTIMATE NI N-LEC GAAS SCHOTTKY-BARRIER DIODES/

The thermal stability of Schottky diode parameters of the fabricated M IS and intimate Ni/n-LEC GaAs Schottky diodes have been investigated u sing current-voltage (I-V) techniques after being annealed in the rang e of 100-600 degrees C for 5 min in N-2 atmosphere. It has been seen t hat the intimate device is thermally mure stable than the MIS device. The I-Ii characteristics of the MIS device were deteriorated after 400 degrees C, while those of the intimate device, after 600 degrees C. T his has been attributed to the fact that the MIS Ni/n-LEC GaAs SBDs he ated from 100 degrees C to 400 degrees C suffers from problems arising from the native oxide layer formed on the GaAs surface. Thus, it has been concluded that a reacted contact is thermodynamically stable in t he absence of the native oxide layer than an unannealed one or than MI S diodes up to a given annealing temperature. Furthermore, we have eva luated the equilibrium interface charge density and the interface stat e charge density distribution from the forward bias I-V characteristic s of the diodes which show MIS diode behavior before and after anneali ng. The results have supported our interpretations related to the idea lity factor and Schottky barrier height. (C) 1998 Elsevier Science B.V . All rights reserved.