Title :
Electrical and charge trapping properties of HfO2/Al2O3 bilayer gate dielectrics on In0.53Ga0.47As substrates
Author :
Ghosh, A.K. ; Das, T. ; Mukherjee, C. ; Bandyopadhyay, A.S. ; Dalapati, G.K. ; Chi, D. ; Maiti, C.K.
Author_Institution :
Dept. of Electron. & ECE, Indian Inst. of Technol., Kharagpur, India
Abstract :
Electrical properties and reliability of bilayer HfO2 (~7nm)/Al2O3 (~3nm) high-k dielectric films prepared by RF sputtering have been studied in detail. It is observed that the bilayer dielectric reduces the frequency dispersion, hysteresis, interface trap charge density (Dit) and gate leakage current density when compared to single layer HfO2. In order to study the degradation mechanisms in Al/HfO2/Al2O3/p-In0.53Ga0.47As and Al/HfO2/p-In0.53Ga0.47As structures as a function of different stress conditions, trapped charge distribution were determined after constant voltage stressing at different bias levels. HfO2/Al2O3 gate stacks exhibited superior electrical performance in terms of trap induced flatband voltage instability and trap charge generation compared to directly deposited HfO2 films on p-In0.53Ga0.47As.
Keywords :
III-V semiconductors; III-VI semiconductors; aluminium compounds; dielectric materials; hafnium compounds; indium compounds; HfO2-Al2O3; In0.53Ga0.47As; RF sputtering; bilayer gate dielectrics; charge trapping property; electrical property; flatband voltage instability; frequency dispersion; gate leakage current density; high-k dielectric films; hysteresis; interface trap charge density; trap charge generation; voltage stressing; Aluminum oxide; Dielectrics; Electron traps; Hafnium compounds; Logic gates; Substrates; Al2O3; HfO2; In0.53Ga0.47As; charge trapping; high-k;
Conference_Titel :
Physical and Failure Analysis of Integrated Circuits (IPFA), 2012 19th IEEE International Symposium on the
Conference_Location :
Singapore
Print_ISBN :
978-1-4673-0980-6
DOI :
10.1109/IPFA.2012.6306299
