Improved Operation Characteristics for Nonvolatile Charge-Trapping Memory Capacitors with High-κ Dielectrics and SiGe Epitaxial Substrates**Supported by the National Science and Technology Major Project of China under Grant No 2013ZX02303007, the National Key Research and Development Program of China under Grant No 2016YFA0301701, and the Youth Innovation Promotion Association of the Chinese Academy of Sciences under Grant No 2016112.

Abstract

A novel high-κ Al2O3/HfO2/Al2O3 nanolaminate charge trapping memory capacitor structure based on SiGe substrates with low interface densities is successfully fabricated and investigated. The memory capacitor exhibits excellent program-erasable characteristics. A large memory window of ∼4 V, a small leakage current density of ∼2 × 10−6 Acm−2 at a gate voltage of 7 V, a high charge trapping density of 1.42 × 1013 cm−2 at a working voltage of ±10 V and good retention characteristics are observed. Furthermore, the programming ( at 10 V for 10 μs) and erasing speeds ( at −10 V for 10 μs) of the fabricated capacitor based on SiGe substrates are significantly improved as compared with counterparts reported earlier. It is concluded that the high-κ Al2O3/HfO2/Al2O3 nanolaminate charge trapping capacitor structure based on SiGe substrates is a promising candidate for future nano-scaled nonvolatile flash memory applications.