The capacitance of a Au-n-GaAs Schottky-barrier diode is given by the relation 1/C^2 =1.57*10^15 to 2.12*10^15v where Ci s expressed in pF and Vis in volts. Taking the diode area to be 0.1 cm2, calculate the built-in potential, the barrier height, and the dopant concentration.