It is shown that the use of CVD WSix in polycides results in a high concentration of fluorine in the gate oxide. The high fluorine concentration in the gate oxide results in increase in the physical gate oxide thickness. The presence of fluorine in CVD WSix results in significant improvement in subthreshold characteristics for both P- and N-MOS submicron devices over sputtered WSix. A reduction in subthreshold slope and leakage current as well as a tighter distribution of these parameters was observed. In addition, improved hot carrier immunity for the CVD WSix process attributed to the fluorine in the gate oxide was observed. Thus CVD WSix should be preferred over sputtered WSix for submicron CMOS devices.
|Number of pages||2|
|Journal||Digest of Technical Papers - Symposium on VLSI Technology|
|State||Published - 1 Dec 1991|
|Event||1991 Symposium on VLSI Technology - Oiso, Jpn|
Duration: 28 May 1991 → 30 May 1991