Question

What is reactive sputtering? Use AlN thin film deposition by DC or RF magnetron reactive sputtering as an example for illustration.

Answer 1

Reactive Sputtering

Reactive Sputtering can be defined as Deposition of Compounds by reactive gases such as Nitrogen or Oxygen into the plasma. These reactive gases are generated by inert gases like Krypton, Xenon and Argon. In this method, Plasma will activate the reactive gas, and there is a reaction between the target material and reactive gas, later it get accumulated on the substrate. The approximate amount of the relative and inert gases are regulated to accomplish the composition control of the resultant film. Reactive Sputtering produces the combination of Carbides, nitrides and Oxides. The reactive sputtering process phenomenon is for the generation of thin films which is in the closely controlled stoichiometry and structure.

Aluminium Nitride thin film deposition by DC or RF magnetron reactive sputtering

On the Surface of Si (100 ) substrate thin films of Aluminium Nitride is deposited by pulsed Direct Current reactive magnetron sputtering which is asymmetric bipolar. This takes place under fluctuating nitrogen flow in a argon and nitrogen gas mixture. The accumulation of the film is identified as Secondary Ion Mass Spectroscopy(SIMS), Spectroscopic ellipsometry, Atomic Force Microscope(AFM and Grazing Incidence X-ray Diffraction(GIXRD). By analysing SIMS it exhibits the existence of Oxygen in the film. The analysis of Spectroscopic ellipsometry shows the evidence of band gap and the refractive index of the film in the extent of 5.0 - 5.48eV and 1.58 - 1.84. The micrographs of Atomic Force Microscope disclosed a microstructure which is very fine grained and with a typical roughness about 6-8nm. The results of GIXRD exhibits (100) reflection of Wurtzite Aln.