Enhanced Electrical Properties of Copper Nitride Films Deposited via High Power Impulse Magnetron Sputtering

High Power Impulse Magnetron Sputtering (HiPIMS) has generated a great deal of interest by offering significant advantages such as high target ionization rate, high plasma density, and the smooth surface of the sputtered films. This study discusses the deposition of copper nitride thin films via HiPIMS at different deposition pressures and then examines the impact of the deposition pressure on the structural and electrical properties of Cu₃N films. At low deposition pressure, Cu-rich Cu₃N films were obtained, which results in the n-type semiconductor behavior of the films. When the deposition pressure is increased to above 15 mtorr, Cu₃N phase forms, leading to a change in the conductivity type of the film from n-type to p-type. According to our analysis, the Cu₃N film deposited at 15 mtorr shows p-type conduction with the lowest resistivity of 0.024 Ω·cm and the highest carrier concentration of 1.43 × 10²⁰ cm^-3. Furthermore, compared to the properties of Cu₃N films deposited via conventional direct current magnetron sputtering (DCMS), the films deposited via HiPIMS show better conductivity due to the higher ionization rate of HiPIMS. These results enhance the potential of Cu₃N films' use in smart futuristic devices such as photodetection, photovoltaic absorbers, lithium-ion batteries, etc.