Photoconductivity in a-SeTe

Abstract

Ab!;tract In-quadrature freqiency-resolved photocurrent (PRPC) measurements were perforined on amorphous SeTe films between 20 K and 290 K. and as a function of excitation intensity. These measuremenrs yield lifetime distributions directly. The results show that the reclimbination kkes place between distant pain and that there is a continuous distribution of stat!s within the mobility gap.

Characteristics of photoconductivity in As-Sb-Se glasses

“…Values for lying between 0.5 and 1 is an indication for a continuous distribution of traps in the energy gap. Similar results have been reported by Kaplan before [20].…”

“…Photoconductivity in each plot is normalized with respect to its maximum value. The photoconductivity response time is calculated using the relation ½ ¾ Ñ Ü where Ñ Ü is the frequency at which photoconductivity shows a peak in its value [20]. From the FRPC data at different intensities of illumination and at different temperatures it is found that the position of Ñ Ü shifts to higher frequencies with increasing temperature or intensity.…”

“…For all the compositions the response time decreases with increase in intensity or temperature. Since the intensity of light excitation is directly proportional to the carrier generation rate , the photoconductivity response time ( ) and can be related by the expression [20][21][22] (6) Variation of ln with ln has been plotted and from the slope of the straight line graph so obtained the value of the exponent has been calculated. The values of for different compositions lie between 0.5 and 1.…”

Second Breakdown of 18V Grounded Gate NMOS induced by the Kirk Effect under Electrostatic Discharge

“…For the range of intensities investigated, we have plotted the variation of ln τ with ln g for the two compositions in figure 5. From the relation τ = Ag ν [17], the value of the exponent ν has been evaluated. For all the samples it lies between 0.5 and 1.…”

“…Carrier lifetime has been measured by the frequency resolved photo current (FRPC) technique [15,16]. The lifetime of the carriers in the sample is related to the frequency corresponding to the peak (f max ) in the frequency dependence of a.c. photoconductivity through the relation τ = 1/2πf max [15,17].…”