Tunneling in quantum confined GaAs ultrashallow sidewall tunnel junctions

Abstract

Temperature dependence of current-voltage (I-V) characteristics of quantum-confined GaAs ultra-shallow sidewall p + n + tunnel junctions has been investigated. The sidewall tunnel junctions with junction depths ranging from 5 nm to 50 nm were achieved by the combination of intermittent injection of TEG/AsH 3 in an ultra high vacuum and a wet etching process of the GaAs growth layer. From the I-V results, abrupt negative differential resistances (NDR) were observed, which relate to direct/indirect tunneling and subband formation. The change in the number instances of NDR and their voltage positions also depended on the junction depth. Mechanisms of tunneling in the present sidewall tunnel junction will be discussed from the point of the sub-band formation in conduction bands.

Sidewall GaAs tunnel junctions fabricated using molecular layer epitaxy

“…To investigate the characteristics of sidewall GaAs tunnel junctions with narrower junction depths, both p + and n + -GaAs of MLE layers were thinned using a H 2 SO 4 The number and voltage positions of sharp steps in the NDR region change with the junction depth [102,103]. Three V S are observed when the junction depth is d = 50 nm, as shown in figure 12(a).…”