Atomic layer deposition temperature dependent minority carrier generation in ZrO(2)/GeO(2)/Ge capacitors

作者：Bethge O^*; Abermann S; Henkel C; Smoliner J; Bertagnolli E; Straif C J; Hutter H

来源：JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B, 2011, 29(1): 01A806.

DOI：10.1116/1.3521472

Low leakage ZrO(2) dielectrics with a thickness of 7 nm are grown by means of atomic layer deposition (ALD) on GeO(2)-passivated Ge substrates. Substrate temperatures during the deposition of ZrO(2) are set to 150 and 250 degrees C, respectively. The influence of the deposition temperature on electrical and structural properties of metal-oxide-semiconductor capacitors is investigated. A significant impact of the ALD temperature on the high frequency capacitance in inversion is demonstrated. The deposition at 250 degrees C leads to a substantial loss of interfacial GeO(x) indicated by time-of-flight secondary ion mass spectroscopy. The loss, which gives rise to trap levels near the oxide/Ge interface, shifts the thermal activation energy of minority carrier generation from a full Ge-bandgap energy to midgap energies.

• 出版日期2011-1