Electrical Characteristics and Annealing Study of Boron-Doped Polycrystalline Diamond Films

Sheng-Hsiung Chen
1995 Journal of the Electrochemical Society  
Annealing processes are an important area of fundamental research within the field of diamond electronic applications. In this study, annealing was applied to as-grown boron-doped diamond films. The current-voltage (I-V) characteristics of the AI/boron-doped diamond films were also investigated. First, the conductivity of films was examined to determine the effect of annealing on boron-doped diamond films. Experimental results indicated that the activation energy for the as-deposited diamond
more » ... eposited diamond films (intrinsic or light boron-doped ) is about 0.38 eV. After annealing, the activation energy did not change. However, the activation energy of the heavily doped films remarkably would change to 0.014 eV after annealing. Next, Fourier transform infrared spectroscopy (FTIR) and cathodoluminescence (CL) were performed to understand more clearly the correlation between the activation energy and the annealing effect on B-doped diamond films. These results revealed that for the lightly B-doped films, the boron atoms were effectively activated at the substitutional site. For the heavily doped case, boron was initially located in an inactive site (e.g., grain boundary, interstitial or clustering sites) and would diffuse into the substitutional site after 900~ annealing. Diamond films, which are wide bandgap and have the highest thermal conductivity, are highly suitable for high-temperature electric device applications. Detailed information concerning the electronic and optical properties of CVD diamond films must be collected and analyzed. Some improvements in the electronic properties of CVD diamond films have recently been made, 1-5 and the activation energy was used to examine the improvement of electrical properties. Masood et al. 6 reported Hall and resistivity meas-
doi:10.1149/1.2048504 fatcat:omwiytbsfzco3ezxqzsikmfdje