AlN thin film growth using electron cyclotron resonance reactive sputtering

In this report, we investigated conditions to deposit stoichiometric aluminium nitride (AlN) thin films grown on (100)-oriented Si substrates under various Ar/N2 gas flow rates at a wide range of temperature from room temperature (RT) to 350°C using electron cyclotron resonance (ECR) reactive sputtering. This study revealed that stoichiometric of thin film can be controlled by N2/Ar flow rate and that stoichiometric N/Al = 1 was archived at N2/Ar = 2. This study also revealed that crystallinity can be controlled by substrate temperature. From RT to 200°C, thin films were amorphous or poly-crystal, at 350°C however, thin film was mainly [110] and [100] AlN. Obtained thin films are densely packed and have very low root mean square (RMS) roughness of 0.41 nm which is much less than other sputtering methods.