Electronic properties of Al/p-Si/C70/Au MIS-type diode

• Electrical characteristics of Al/p-Si/C70/Au confirm that is a metal–insulator–semiconductor diode.
• The higher values of the ideality factor are due to barrier height inhomogeneities.
• The zero-bias mean barrier height ϕ¯bo was found to be 1.06 eV.

The electrical characteristics of the Al/p-Si/C70/Au diode were investigated by current–voltage and capacitance–voltage measurements. The current–voltage characteristics confirm that the diode is a metal–insulator–semiconductor type device. The decrease in ideality factor and increase in barrier height values of the diode were observed with temperature. This behavior was explained on the basis of Schottky barrier height inhomogeneities. The zero-bias mean barrier height ϕ¯bo and Richardson values for the diode were found to be 1.06 eV and 33.12 A/cm2 K2, respectively. The obtained Richardson constant (A* = 33.12 A/cm2 K2) is in agreement with the theoretical value of A* = 32 A/cm2 K2. The interface state density properties of the diode were analyzed and the shape of the interface state density is changed with temperature. The ϕB value obtained from C–V measurement is higher than that of ϕB value obtained from I–V measurements. The discrepancy between ϕB(C–V) and ϕB(I–V) values was explained by distribution of Schottky barrier height due the inhomogeneities.

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