Comparison of CPM, PDS and Optical Transmittance of Amorphous Carbon Nitride Films Made by a Nitrogen Radical Sputter Method
Abstract
Amorphous carbon nitride films a-CN(x), deposited in our laboratory by a radical sputter method, show high photosensitivity P(s), where P(s) is the ratio of photoconductivity sigma(p) and dark-electrical conductivity omega(d-)Cid A-CN(x) made a layer-by-layer method, LLa-CN(x), has the highest photosensitivity in our various preparation conditions. The photoconductivity in a- CN(x) and LLa-CN(x) shows dependence on photon energy in the range 2 eV to 6.2 eV. The constant photocurrent method (CPM), photothermal deflection spectroscopy (PDS) and optical transmittance spectra are used to obtain the information in the optical energy band gap and defect states, A-CN(x) and LLa-CN(x) are good photoconductors especially at energy higher than 3 eV. Therefore it is not difficult to obtain CPM spectra in the high photon energy region. CPM spectra are obtained by dc- and ac- measurements. The value of the absorption coefficient a spectra obtained by dc-CPM is larger than that of ac-CPM, which increases with increasing frequency of the measurement. In this paper, CPM data is used to discuss a model of density of states (DOS) of a-CN(x) by comparison with PDS and optical transmittance spectra.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2001
- Accession Number
- ADP012168
Entities
People
- Hitoe Habuchi
- Shoji Nitta
- Takashi Katsuno
Organizations
- Gifu University