Boron Doped A-Si,C:H Grown by Reactive Magnetron Sputtering from Doped Targets

Applied Physics Letters

et al. 1997

We deposited hydrogenated amorphous silicon-based thin film transistors using dc reactive magnetron sputtering at a substrate temperature of 125 °C. We characterize the structural properties of the a-Si:H channel and a- SiNx:H dielectric layers using infra-red absorption, thermal hydrogen evolution, and refractive index measurements, and evaluate the electrical quality using conductivity, capacitance–voltage, and leakage current measurements. Inverted staggered thin film transistors made with these layers exhibit a field effect mobility of 0.3 cm2/V s, a Ion/Ioff ratio of 5×105, a subthreshold slope of 0.8 V/decade, and a threshold voltage of 3 V.

mentioning

confidence: 99%

An amorphous silicon thin film transistor fabricated at 125 °C by dc reactive magnetron sputtering

McCormick

Weber

Applied Physics Letters

et al. 1997

Does a dipole layer at the p–i interface reduce the built-in voltage of amorphous silicon p–i–n solar cells?

Nuruddin

Applied Physics Letters

1997

The open-circuit voltage of amorphous silicon p–i–n solar cells is 0.1–0.3 V less than the total Fermi level shift in the p- and n-type layers. It was hypothesized that a dipole layer at the p–i interface reduces the potential drop across the i-layer. We determine the electrostatic potential profile using an in situ Kelvin probe during incremental depositions of p-type a-Si,C:H and undoped a-Si:H layers by direct current reactive magnetron sputtering. We confirm the existence of a dipole layer, but which produces a potential loss of only ∼20 mV. Thus, most of the “missing” voltage in solar cells must have other origins.

Low temperature fabrication of amorphous silicon thin film transistors by dc reactive magnetron sputtering

McCormick

Weber

Journal of Vacuum Science &Amp; Technology A: Vacuum, Surfaces, and Films

et al. 1997

Articles you may be interested inPlasma enhanced metalorganic chemical vapor deposition of amorphous aluminum nitride Structural, optical, and electrical properties of hydrogenated amorphous silicon germanium alloysWe deposit hydrogenated amorphous silicon ͑a-Si:H͒ and hydrogenated amorphous silicon nitride (a-SiN x :H) films using dc reactive magnetron sputtering at 125 and 230°C substrate temperatures. We characterize the structural properties using infrared absorption, thermal hydrogen evolution, and refractive index measurements, and evaluate the electrical quality using capacitance-voltage and leakage current measurements. Nitride layers deposited at both temperatures have dominant N-H bonding with hydrogen concentration approximately 10 22 /cm 3 . Metal-insulator-semiconductor devices have been fabricated on c-Si and show electrical leakage of Ͻ 5 ϫ 10 Ϫ8 A/cm 2 at 3 MV/cm field, flat band voltage magnitude Ͻ 1 V, and hysteresis Ͻ 2 V. Low temperature a-Si:H films show monohydride dominant bonding. The photo-to dark conductivity ratio is 5 ϫ 10 5 for films deposited at 125°C. Inverted staggered thin film transistors have been fabricated with the optimized layers. Thin film transistors deposited at 230°C have a field effect mobility of 0.8 cm 2 /V s, an I on /I off ratio of 5 ϫ 10 5 , a subthreshold slope of 1.2 V/decade, and a threshold voltage of 4 V; those deposited at 125°C have a field effect mobility of 0.3 cm 2 /V s, an I on /I off ratio of 5 ϫ 10 5 , and a threshold voltage of 3 V.