A comprehensive study of the phosphorus dosage and annealing condition dependencies of boron-penetration and poly-depletion is presented. The experimental results show that the boron-penetration in BF2 implanted poly-gate is significantly reduced as the dose of co-implanted phosphorus increases. The phosphorus dose of about 1.5×1015cm-2 in p+-poly gate can effectively retard the penetration of boron in BF2 3 to 5×1015cm-2 doped poly gate under 900°C, 60min annealing (30min reflow anneal, and 30min post-contact implant anneal). The performance of boron-penetration-free phosphorus co-implanted p+-poly gate MOSFETs is also shown to be much better than the device with boron-penetration. In arsenic Co-implanted p-poly gate, it also appears that arsenic co-implant would also retard boron penetrating through thin gate oxide. An optimal and effective gate processing for preventing boron-penetration is proposed for dual-gate CMOS devices.
|Number of pages||4|
|State||Published - 1 Dec 1995|
|Event||Proceedings of the 1995 International Symposium on VLSI Technology, Systems, and Applications - Taipei, Taiwan|
Duration: 31 May 1995 → 2 Jun 1995
|Conference||Proceedings of the 1995 International Symposium on VLSI Technology, Systems, and Applications|
|Period||31/05/95 → 2/06/95|