New Transition Spectroscopy
Original Publication Date: 1985-Feb-01
Included in the Prior Art Database: 2005-Feb-18
A new method for characterizing traps in the forbidden gap of a silicon MOS structure is described and consists in measuring capacitance transients caused by abruptly varying electrical fields. These capacitance responses carry the effect of electronic state transitions, called "traps", when they appear within the forbidden gap. Lang's method developed in 1974, known Deep Level Transition Spectroscopy (D.L.T.S.), has been applied to P-N junctions and Schottky diodes and consists in analyzing a thermal spectrum given by the following function: f(T) = C(t1) - C(t2) where C(ti) is the measure of the structure capacitance at time ti . The capacitance transients are supposed to be of the exponential type, C(t) : Co exp-t/t, where t is the relaxation time.