Electrical Characteristics Of Hole Resonant Tunneling Diodes With High Ge Fraction (x > 0.4) Si/strained Si_(1-x)ge_x/si(100) Heterostructure

摘要

Effectiveness of a Ge fraction modulated spacer in hole resonant tunneling diodes (RTDs) with Si/strained Si_(1-x)Ge_x heterostructures epitaxially grown on Si(100) was investigated to improve the electrical characteristics at higher temperatures. Electrical characteristics measured for 30 RTDs, with the modulated spacer at higher Ge fraction (x = 0.48) on a single wafer, show that the deviation of the peak current and voltage at the resonant peak falls in ranges of ±25% and ±10%, respectively. For the RTDs, negative differential conductance (NDC) characteristics are obtained even at higher temperatures around 230 K than that for the RTDs with x = 0.42. The result indicates that the introduction of higher Ge fraction is effective for NDC in RTD at higher temperature.