Title :
Effects of deposition temperature on the oxidation resistance and electrical characteristics of silicon nitride
Author :
Yoshimaru, Masaki ; Inoue, Nobuhiko ; Tamura, Hiroyuki ; Ino, Masayoshi
Author_Institution :
VLSI Res. & Dev. Center, Oki Electr. Ind. Co. Ltd., Tokyo, Japan
fDate :
10/1/1994 12:00:00 AM
Abstract :
A study was made of the effects of deposition temperature on the oxidation resistance and electrical characteristics of silicon nitride. It was found that silicon nitride below a certain limit thickness has no oxidation resistance. This threshold falls as the deposition temperature is lowered. 3-nm-thick silicon nitride deposited at 600°C has sufficient oxidation resistance For wet oxidation at 850°C, while 5 nm film deposited at 750°C has no oxidation resistance. The electrical characteristics also improve as the deposition temperature is lowered. 6-nm-thick silicon nitride deposited at 600°C shows a TDDB lifetime that is about two orders longer than that of 6-nm-thick silicon nitride deposited at 700°C. It was also found that the silicon nitride transition layer which is deposited at the initial stage of deposition influences the oxidation resistance and electrical characteristics of thin silicon nitride. It was concluded that lowering the deposition temperature reduces the influence of the transition layer and improves the oxidation resistance and electrical characteristics of thin silicon nitride
Keywords :
DRAM chips; chemical vapour deposition; dielectric thin films; electric breakdown of solids; oxidation; silicon compounds; 3 to 6 nm; 600 to 850 degC; DRAM dielectric film; LPCVD; Si3N4; TDDB lifetime; deposition temperature; electrical characteristics; oxidation resistance; silicon nitride; transition layer; wet oxidation; Capacitors; Degradation; Dielectric thin films; Electric resistance; Electric variables; Oxidation; Random access memory; Semiconductor films; Silicon; Temperature;
Journal_Title :
Electron Devices, IEEE Transactions on
