Title :
Electrical characteristics of highly reliable ultrathin hafnium oxide gate dielectric
Author :
Kang, Laegu ; Byoung Hun Lee ; Qi, Wen-Jie ; Jeon, Yongjoo ; Nieh, Renee ; Gopalan, Sundar ; Onishi, Katsunori ; Lee, Jack C.
Author_Institution :
Microelectron. Res. Center, Texas Univ., Austin, TX, USA
fDate :
4/1/2000 12:00:00 AM
Abstract :
Electrical and reliability properties of ultrathin HfO/sub 2/ have been investigated. Pt electroded MOS capacitors with HfO/sub 2/ gate dielectric (physical thickness /spl sim/45-135 /spl Aring/ and equivalent oxide thickness /spl sim/13.5-25 /spl Aring/) were fabricated. HfO/sub 2/ was deposited using reactive sputtering of a Hf target with O/sub 2/ modulation technique. The leakage current of the 45 /spl Aring/ HfO/sub 2/ sample was about 1/spl times/10/sup -4/ A/cm/sup 2/ at +1.0 V with a breakdown field /spl sim/8.5 MV/cm. Hysteresis was <100 mV after 500/spl deg/C annealing in N/sub 2/ ambient and there was no significant frequency dispersion of capacitance (<1%/dec.). It was also found that HfO/sub 2/ exhibits negligible charge trapping and excellent TDDB characteristics with more than ten years lifetime even at V/sub DD/=2.0 V.
Keywords :
MOS capacitors; annealing; dielectric hysteresis; dielectric thin films; hafnium compounds; leakage currents; semiconductor device breakdown; semiconductor device reliability; sputtered coatings; 13.5 to 25 A; 2 V; 45 to 135 A; 500 C; N/sub 2/; N/sub 2/ ambient; O/sub 2/; O/sub 2/ modulation technique; Pt electroded MOS capacitors; Pt-HfO/sub 2/-Si; TDDB characteristics; annealing; breakdown field; electrical characteristics; highly reliable gate oxide; hysteresis; leakage current; reactive sputtering; reliability properties; ultrathin HfO/sub 2/; ultrathin gate dielectric; Annealing; Dielectrics; Electric breakdown; Electric variables; Frequency; Hafnium oxide; Hysteresis; Leakage current; MOS capacitors; Sputtering;
Journal_Title :
Electron Device Letters, IEEE
