In:
Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena, American Vacuum Society, Vol. 17, No. 4 ( 1999-07-01), p. 1831-1835
Abstract:
High resolution soft x-ray photoelectron spectroscopy with synchrotron radiation is used to study the interfaces of SiO2/Si(111), SiO2/Si(100), Si(111)/Si3N4, and SiO2/Si3N4 for device-quality ultrathin gate oxides and nitrides. The thin oxides and nitrides were grown by remote plasma deposition at a temperature of 300 °C. Aftergrowth samples were further processed by rapid thermal annealing for 30 s at various temperatures from 700 to 950 °C. The Si(111)/Si3N4 samples were air exposed and formed a thin ∼6 Å SiO2 layer with a Si(2p) core-level shift of 3.9 eV, thus allowing us to study both the Si(111)/Si3N4 and SiO2/Si3N4 interfaces with a single type of sample. We obtain band offsets of 4.54±0.06 eV for SiO2/Si(111) and 4.35±0.06 eV for SiO2/Si(100) with film thicknesses in the range 8–12 Å. The Si(111)/Si3N4 nitrides show 1.78±0.09 eV valence-band offset for 15–21 Å films. This value agrees using the additivity relationship with our independent photoemission measurements of the nitride–oxide valence-band offset of 2.66±0.14 eV. However, we measure a substantially larger SiO2/Si3N4 ΔEV value of 3.05 eV for thicker (∼60 Å) films, and this indicates substantial differences in core-hole screening for films of different thickness due to additional silicon substrate screening in the thinner (15–21 Å) films.
Type of Medium:
Online Resource
ISSN:
1071-1023
,
1520-8567
Language:
English
Publisher:
American Vacuum Society
Publication Date:
1999
detail.hit.zdb_id:
3117331-7
detail.hit.zdb_id:
3117333-0
detail.hit.zdb_id:
1475429-0
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