Extremely low-leakage GaAs P-i-N junctions and memory capacitors grown by atomic layer epitaxy

Leakage-limited P-i-N-i-P charge storage capacitors demonstrate a 1/e storage time of over 30 min at room temperature, corresponding to a current density of less than 50 pA/cm/sup 2/ at 1-V reverse bias for a 160*140- mu m/sup 2/ capacitor. These storage times are comparable to those of the best MBE-grown structures reported to date. For the diodes tested, which range in size from 4*10/sup -4/ to 4.9*10/sup -5/ cm/sup 2/, leakage is dominated by generation around the etched diode perimeter. The relatively small bulk generation current is evidence of the high quality of the atomic layer epitaxy (ALE)-grown junctions. >