Other Large-Signal Charge-Pumping Techniques

The variations of the emission times have also an influence on the charge-pumping current during the course of experiment in other charge-pumping methods used to scan the lateral trap profile:

• method I proposed in [374], where the gate pulse is kept constant with respect to the drain and source, while varies (namely varies with respect to other three terminals).
• the two-pulse modification of method II [9]. In this technique pulses of amplitude are applied on the drain contact with respect to the bulk. The source and drain are connected together. These pulses are in opposite phase with the standard gate-bulk pulses. During of the gate pulse the drain pulse has a value , as in method II. During the drain/source-bulk junctions are not biased. As a consequence, traps are always filled at the same effective gate bias, independently of the reverse bias ; the oxide field remains the same at each point of the interface during the course of experiment. Regarding the parasitic effect, it should be reduced in this technique in comparison with method II.
• the technique with the fixed gate base level and variable top level [273][34] (with respect to -channel devices).
• the method with the fixed gate top level and variable base level [480][288] (with respect to -channel devices).
• the technique similar to method II, but the drain-bulk and the source-bulk reverse biases are varied independently [423][272][271]. The bias between drain and source is kept small (to ). By this approach the trap distributions at the source and drain side can be extracted independently of each other.