i use Ta2O5 as hydrogen conductor. Ta2O5 is reactive dc sputtered. i change the expermental parameters such as gas pressure and power. but when i sputtered Pt on Ta2O5, Ta2O5 acts as like resistor not insulator. i also tried 2 um thick Ta2O5 to enhance its density. but it doesn't work. thanks for reading it. ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com