Behavior of the discrete states observed through detailed analyses of TSC curves

In order to make the electronic transport mechanism in organic substances clear in detail, the thermally stimulated current (TSC) method is very effective. From the TSC method, three parameters such as an energy depth E_t [eV] of the carrier trap site, a preexponential parameter (or an escape frequency factor) ν [s^-1 ] and a charge carrier density n_t [m^-3] relating to the phenomena, can be estimated. We have completed some theories that enable us to analyze in detail TSC data obtained experimentally. One of them, the asymptotic estimation method (AEM) originally proposed by us, enables us to evaluate these three parameters accurately. And this has been expanded extensively to estimate 3N parameters, through an exact auto-separation (AS) method of various composite TSC curves and through the reconstruction (RC) method of TSC curves with no peak obtained by partially repeated heating cooling procedures. Where N is the number of the single TSC curve of the first-order included in the objects. The fine advantages are that these expanded theories have higher accuracy than 4 significant figures. Then, detail analyses of discrete states became possible by using both methods