氮化硼—矽介面之電氣特性

Abstract

Boron nitride thin films on silicon substrate were prepared by electron-beam evaporation techniques for wide range of substrate temperature control and different temperature nitridind annealing processes. It is found that the interface charge of boron nitride thin film on silicon gives the negative surface state charge of 2.5*10^11/cm^2 and 7.6*10^11/cm2 for n- and p-type silicon substrate, respectively, the flat-band voltage is always less than one volt. The surface state density of MIS capacitor structure is studied by the differentiation method, and the trapped charge rearrangements due to B-T testing are interpreted. The boron nitride thin film properties are also studied by I-V characteristics. It is found that the precipitates of B2O3 will give the ohmic conduction current with activation energy of 0.395 ev for n-type sample at low positive gate voltage (electric field less than 10^4v/cm), the schottky emission conduction rather than the Frenkel-Poole emission is observed at high electric field (>10^4v/cm) for both n- and p-type silicon MIS capacitor structure. The boron nitride p- and n-channel MISFET are fabricated by using the conventional planar technology incorporated with the electron-beam evaporation of boron- nitride gate insulator layer. The electrical properties and possible device applications are examined.