Depletion Layer Parameters of Al-MoO3-P-CdTe-Al MOS Structures

The Al-MoO3-P-CdTe-Al MOS sandwich structures
were fabricated by vacuum deposition method on cleaned glass
substrates. Capacitance versus voltage measurements were performed
at different frequencies and sweep rates of applied voltages for oxide
and semiconductor films of different thicknesses. In the negative
voltage region of the C-V curve a high differential capacitance of the
semiconductor was observed and at high frequencies (<10 kHz) the
transition from accumulation to depletion and further to deep
depletion was observed as the voltage was swept from negative to
positive. A study have been undertaken to determine the value of
acceptor density and some depletion layer parameters such as
depletion layer capacitance, depletion width, impurity concentration,
flat band voltage, Debye length, flat band capacitance, diffusion or
built-in-potential, space charge per unit area etc. These were
determined from C-V measurements for different oxide and
semiconductor thicknesses.


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