Title :
Rugged surface poly-Si electrode and low temperature deposited Si/sub 3/N/sub 4/ for 64 Mbit and beyond STC DRAM cell
Author :
Yoshimaru, M. ; Miyano, J. ; Inoue, N. ; Sakamoto, A. ; You, S. ; Tamura, H. ; Ino, M.
Author_Institution :
Oki EIectr. Ind. Co. Ltd., Tokyo, Japan
Abstract :
Describes the novel technologies of poly-Si and Si/sub 3/N/sub 4/ film which are used for the storage capacitor electrode and also dielectric film of a DRAM STC (stacked capacitor cell), respectively. Poly-Si film deposited at about 570 degrees C has a rugged surface. It is found that 0.1 mu m poly-Si film deposited at 570 degrees C has a 2.5-times-larger surface area than film deposited at 620 degrees C. It is also found that Si/sub 3/N/sub 4/ film deposited at 600 degrees C has a higher oxidation resistance than film deposited at 750 degrees C. By the use of the rugged surface poly-Si film and the 6.3 nm SiO/sub 2/-equivalent-thick Si/sub 3/N/sub 4/ film, an STC which has a storage capacitance equal to that of the conventional STC cell with 2.5 nm SiO/sub 2/-equivalent-thick dielectric film can be realized.<>
Keywords :
CVD coatings; DRAM chips; dielectric thin films; elemental semiconductors; semiconductor thin films; silicon; silicon compounds; 0.1 micron; 570 to 750 degC; 64 Mbit; DRAM STC; Si; Si/sub 3/N/sub 4/; dielectric film; oxidation resistance; polysilicon film; storage capacitor electrode; surface area; Capacitance; Capacitors; Dielectric films; Electrodes; Oxidation; Random access memory; Semiconductor films; Surface resistance; Temperature;
Conference_Titel :
Electron Devices Meeting, 1990. IEDM '90. Technical Digest., International
Conference_Location :
San Francisco, CA, USA
DOI :
10.1109/IEDM.1990.237113
