Title :
Low temperature MOCVD of BST thin film for high density DRAMs
Author :
Cho, H.-J. ; Park, J.B. ; Yu, Y.S. ; Roh, J.S. ; Yoon, H.K.
Author_Institution :
Memory R&D Div., Hyundai Electronics Industries Co. Ltd, Kyoungki, South Korea
Abstract :
The deposition characteristics of BST thin films by liquid source MOCVD at 410°C on 8-inch diameter Pt/SiO2/Si substrate were investigated using O2/N2O/NH3 mixture as oxidants. Using N2O gas only as an oxidant around 410°C is not adequate because of high C content in deposited BST films. The introduction of NH3 with O2 is highly effective on raising deposition rate, Ti/(Ba+Sr+Ti), and within wafer uniformity of Ti. The 2-step anneal process consisting of high temperature RTA in low pressure before top electrode deposition and then furnace anneal after top Pt patterning in N2 atmosphere is effective on the reduction of Tox (equivalent oxide thickness) and leakage current of BST films with minimizing thermal budget of post anneal process. The RTA at 700°C of 300-Å-thick BST films annealed at 500°C reduces Tox from 12.3 to 7.0 Å
Keywords :
DRAM chips; MOCVD; annealing; barium compounds; dielectric thin films; rapid thermal annealing; strontium compounds; (BaSr)TiO3; 410 C; 500 C; 700 C; 8 inch; BST thin film; O2/N2O/NH3 oxidant; Pt/SiO2/Si substrate; RTA; capacitor dielectric material; equivalent oxide thickness; furnace annealing; high density DRAM; leakage current; liquid source MOCVD; low temperature deposition; thermal budget; Annealing; Binary search trees; Electrodes; Furnaces; MOCVD; Semiconductor thin films; Sputtering; Substrates; Temperature; Transistors;
Conference_Titel :
Applications of Ferroelectrics, 2000. ISAF 2000. Proceedings of the 2000 12th IEEE International Symposium on
Conference_Location :
Honolulu, HI
Print_ISBN :
0-7803-5940-2
DOI :
10.1109/ISAF.2000.941511
