Hafnium oxide (HfO 2 ) thin films were deposited from tetrakis͑ethylmethylamino͒hafnium ͑TEMAH͒ and ozone (O 3 ) by atomic layer deposition ͑ALD͒ on 200 mm silicon wafers. The O 3 half-reaction shows good saturation behavior. However, gradual surface saturation is observed for the TEMAH half-reaction. Within wafer non-uniformity of less than 1% and step coverage of about 100% were achieved for trenches with aspect ratio of around 40:1. The film thickness increased linearly as the number of cycles increased. From susceptor temperatures of 160-420°C, the lowest deposition rate ͑Å/cycle͒ and the highest refractive index is observed at 320°C. The atomic ratio of hafnium to oxygen determined by Rutherford backscattering is 1:2.04 for the films deposited at 320°C. The carbon and hydrogen content determined by secondary ion mass spectroscopy ͑SIMS͒ decreased as the susceptor temperature increased from 200 to 320°C. Lower carbon and hydrogen levels were obtained in the control films made with H 2 O than the films made with O 3 . A reaction mechanism of the TEMAH ϩ O 3 ALD process is discussed. The results show that an O 3 -based ALD HfO 2 deposition is promising for microelectronic applications.

Abstract. We establish estimates for the number of points that belong to an aligned box in (R/Z) N in terms of certain exponential sums. These generalize previous results that were known only in case N = 1.

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