Generation-recombination-induced nonlinear characteristics of solid-state bipolar devices

Abstract

Generation-recombination processes have been studied with the use of a phenomenological approach. The approach is in principle based on the combined mechanisms involved in the dominant deep-level traps and in radiative and nonradiative processes in these devices. It is possible with the use of the approach to predict different types of carrier transition phenomena under zero- and nonzero-bias conditions. Carrier phase diagrams have been produced which can depict, in classified form, all possible transitions as a function of the coefficients involved in the phenomena. Attempts have also been made to deal with the generation-recombination processes associated with the midgap single-level impurities, in line with Shockley–Hall–Read theory. The approach leads to the development of a two-root model which demonstrates the existence or nonexistence of hysteresis in the I-V characteristics of devices. Detailed mathematical results and physical modeling have been presented. Graphical representation and experimental evidence of the model have also been produced.

Annealing and transient effects in some GaAs diodes

“…The curve (a) stands for measurements before annealing. It shows a hysteresis loop with m 2 which is in good agreement with the two roots model [15]. The curve (b) stands for the measurement for the diode annealed at low temperature (77 K) for 8 hours (see section 2).…”

“…The magnitude of m is of the order of 1.3 which is ideal [19]. The uniform value indicates the absence of active generation-recombination induced phenomena in the mid-gap traps, impurities etc [15], at least in the initial (low voltage) part of the ln I -V curves (not shown here). The uniform m values also indicate the absence of the influence of the waiting (transient) times.…”

“…Since the diodes in the present study were commercially available ones, the necessary technical data are lacking but the object of the present study was to find out how the characteristics of these diodes could be changed or modified following the two roots model [15][16][17]. TSC (thermally stimulated current) measurements [13,14] have been carried out under a reverse bias V = −0.1 V and the heating rate measurement was constantly recorded in parallel over the whole measurement temperature range.…”

“…This leads to a hysteresis in the characteristics in the region where the ideality factor (m) is of the order of 2. The transition between the appearance of the hysteresis and its disappearance is predictable which was in fact depicted in a phase diagram in [15] and the model has been discussed in full detail in [15][16][17]. The usefulness of the model is however twofold:…”

“…E t represents a change in the trap-level that might occur during the annealing processes (see next section). These effects will be discussed on the line of the two roots model (TR model) [15][16][17]. The model will however be outlined here briefly.…”