Low temperature microcrystalline silicon thin film resistors on glass substrates

Doped microcrystalline silicon (mu c-Si) thin film resistors have been processed at low temperatures (<300 degrees C) using direct deposition in an electron cyclotron resonance high density plasma tool. These n-type doped mu c-Si films (n-type mu c-Si) have been deposited on Coming 1737 glass at electrode temperatures of 100-300 degrees C. The impact of deposition parameters on the conductivity and crystallinity of the films has been investigated. We obtained conductive films at electrode temperatures as low as 100 degrees C at higher RF substrate bias (30 W) and silane flow rate (3 sccm). Thin film resistors were fabricated using films deposited under these conditions. The temperature coefficient of resistivity of these devices is less than 1%/K. The activation energies for these devices are 0.07-0.13 eV in the 25-150 degrees C range. A critical minimum deposition time was found. in excess of which the film conductivity does not change. (C) 2000 Elsevier Science Ltd. All rights reserved.