This article reports the electrical characteristics of p-n junction diodes that were formed by directly depositing a Sb-doped n-type epilayer on a p-type substrate by using a de-bias electron cyclotron resonance plasma sputtering system at a low temperature of 400 degreesC and a conventional vacuum of 5 X 10(-7) Torr. The reverse current density of the n(+) -p junctions diodes depends on deposition gas pressures and substrate biases. The n(+)-p junction diodes exhibit, under optimum conditions, a reverse current density as low as 9.5X 10(-9) A/cm(2) at a reverse bias voltage of 5 V and an ideality factor of 1.05. The excellent characteristics of the n+-p junction diode are due to the integrity of interface between ni epilayer and p-type Si substrate.