Title :
Formation of high quality ultrathin oxide/nitride (ON) stacked capacitors by in situ multiple rapid thermal processing [DRAM cells]
Author :
Han, L.K. ; Yoon, G.W. ; Kim, J. ; Yan, J. ; Kwong, D.L.
Author_Institution :
Dept. of Electr. & Comput. Eng., Texas Univ., Austin, TX, USA
Abstract :
High quality, ultrathin (<30 /spl Aring/) SiO/sub 2//Si/sub 3/N/sub 4/ (ON) stacked film capacitors have been fabricated by in situ rapid-thermal multiprocessing. Si/sub 3/N/sub 4/ film was deposited on the RTN-treated poly-Si by rapid-thermal chemical vapor deposition (RTCVD) using SiH/sub 4/ and NH/sub 3/, followed by in situ low pressure rapid-thermal reoxidation in N/sub 2/O (LRTNO) or in O/sub 2/ (LRTO) ambient. While the use of low pressure reoxidation suppresses severe oxidation of ultrathin Si/sub 3/N/sub 4/ film, the use of N/sub 2/O-reoxidation significantly improves the quality of ON stacked film, resulting in ultrathin ON stacked film capacitors with excellent electrical properties and reliability.<>
Keywords :
DRAM chips; capacitors; chemical vapour deposition; dielectric thin films; integrated circuit reliability; integrated circuit technology; nitridation; oxidation; rapid thermal processing; silicon compounds; DRAM cells; SiO/sub 2/-Si/sub 3/N/sub 4/; SiO/sub 2//Si/sub 3/N/sub 4/; electrical properties; low pressure reoxidation; multiple rapid thermal processing; rapid-thermal chemical vapor deposition; rapid-thermal reoxidation; reliability; stacked film capacitors; ultrathin oxide/nitride stacked capacitors; Capacitance; Capacitors; Chemical vapor deposition; Degradation; Dielectric measurements; Oxidation; Random access memory; Rapid thermal processing; Thickness measurement;
Journal_Title :
Electron Device Letters, IEEE
