Multilayer photoconductors

TOF Measurements in Selenium-Based Amorphous Multilayer Photoconductors 66... 

Complex formation occurs in MeN02 solution and the solution is then applied to the surface to be coated. Washing with water removes the Lewis acid leaving a thin film of the photosensitive pigment. The Lewis acid pigment solubilization (LAPS) technique has been used to fabricate multilayer photoconductors and appears to have a promising technological future. 

Sugi M, Saito M, Fukui T and lizima S 1983 Effect of dye concentration in Langmuir multilayer photoconductors... 

The coating chamber was equipped with a set of independently controlled stainless steel boats and a shutter system to enable the fabrication of multilayer structures. Pure selenium pellets were loaded into one boat and As Sei alloys into another. The two sources were evaporated sequentially (without breaking the vacuum) at boat temperatures of about 450 K. Typical coating rates were l j,m/min. After evaporation, they were allowed to anneal over several weeks in the dark at room temperature. During this period, due to structural bulk relaxation, most physical properties of the photoconductor film become stabilized. The compositions of the deposited films were determined by electron probe microanalysis, and the compositions quoted (0 < X < 0.20) are accurate to within 0.5 at.%. By shuttering the beginning and the end of the evaporation, a uniform arsenic composition across the film thickness can be obtained. In all experiments, a transparent gold electrode ( 300 jm thick) was used as the top contact. 

Maximum photosensitivity was obtained for two layer system containing a thin PVC-TNF layer covered by thick PVC layer [73] (Fig. 14). Here CT complex realizers photogeneration function and PVC the transport one. Memory effects, p-n transitions, and others may be obtained for multilayers and polydispersed systems. The photosensitivity of the last ones strongly depend from the incapsulation velocity of the inorganic photoconductors in polymer matrixes [79-81]. 

The most commonly used polymers in this field are the ones containing carbazole. Prospective uses may be connected with heterocycle heterogeneous and multilayer systems with sensitivities of up to 102m2 J"1 and resolutions 103 mm-1. The partial transparency permits the use of polymeric photoconductors in microfilms and related fields. The sensitivity of such materials is of the order 1 m2 J 1, charge potential 250-400 V, resolution 70-500mm-1, and transparency 65-70%. 

Considerable interest in polydiacetylenes multilayers as possible semiconductors and photoconductors has been expressed. A preliminary study of C C COOH and C C COOLilayers deposited on lock and key electrodes has been undertaken. Samples exhibited... 

The photoconductor-liquid-crystal sandwiches incorporate either a dc driving source or a somewhat complicated multilayer structure. Maydan, Melchior, and Kahn have circumvented both of these aspects by utilizing the thermo-optic properties of nematic-cholesteric mixtures reported by Soref. He showed that nematic-cholesteric... 

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