Helium-Charged Titanium Films Deposited by Pulsed Laser Deposition in an Electron-Cyclotron-Resonance Helium Plasma Environment

Titanium thin films incorporated with helium are produced by pulsed laser deposition in an electron cyclotron resonance helium plasma environment. Helium is distributed evenly in the film and a relatively high He/Ti atomic ratio (～20%) is obtained from the proton backscattering spectroscopy. This high concentration of helium leads to a surface blistering which is observed by scanning electron microscopy. Laser repetition rate has little influence on film characters. Substrate bias voltage is also changed for the helium incorporating mechanism study, and this is a helium ion implantation process during the film growth. Choosing suitable substrate bias voltage, one can avoid the damage produced by ion implantation, which is always present in general implantation case.