Conformal Doping for FinFETs by Self-Regulatory Plasma Doping. 16 nm. Bell Shockley Bardeen Brattain 3. Kilby 1959 Noyce 3) MOS FET

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1 Conformal Doping for FinFETs by Self-Regulatory Plasma Doping Yuichiro Sasaki Katsumi Okashita Bunji Mizuno FETField Effect Transistor SRPD : Self-Regulatory Plasma Doping PD : Plasma Doping 11 %FETFET SRPDhigh-k FETpMOS FinFETsFET A new Self-Regulatory Plasma Doping (SRPD) technique with B 2 H 6 /Helium gas plasma has been successfully developed that provides conformal doping for fins. Manufacturing level of process controllability (<1 % per dose) for the new SRPD has been realized, and the advantages of the SRPD have been verified with FinFETs with metal/high-k gate stack for the first time. Short Channel Effect (SCE) improvement for FinFETs is clearly obtained. Bell ShockleyBardeenBrattain3 Kilby 1959 Noyce Hoerni 1), 2) MOS FET Metal Oxide Semiconductor Field Effect Transistor p 3) MOS FET 40 MOS FET IEDM08 1 4) Intel Corp. 22 nm FET 16 nm FET FET FET1 FETFET Schematic of planar type FET and fin type FET, respectively

2 FET 5) 6) 5), 7) 2 2 FETV TSAT 1 V TSAT 8) FET PD 7), 9)-12) Vapor Phase Deposition (VPD) Atomic Layer Doping (ALD) 13) 2 7) PD1.4 7) VPDALD ) PD 13) VPDALDPD SRPD SRPDPD PD SRPD 3.1 SRPDPD 3 RF B 2 H 6 He RF FinFETs Issue of resist shadowing with ion implant technology Plasma doping equipment

3 PD 14) SRPD 2E15 cm -2 Al3E10 cm -2 SRPD 3.2 PD 4a SEMScanning Electron Microscope 9 nm cpd 6E15 cm -2 FET 5E14 cm -2 3E15 cm -2 PDc FET5 nm20 nm 5 nm PD SRPD SPRD SEM images; (a) before and (b) after SRPD process (this work), and (c) after conventional PD PD SRPD 1 4bSRPDc a 15) 5SRPDspike RTA1000 2D Scanning Spreading Resistance Microscopy SSRM 15) 2E SRPD SSRM measurement of fin structures that has been doped with SRPD process. R s and X j of top surface measured at other planar wafer are 1300 /sq. and 18.9 nm, respectively.

4 150 nm SSRM20 nm 13 SSRM X j X j 5 SIMSSecondary Ion Mass Spectrometry X j 18.9 nm 5E18 cm -3 SRPD 1 20 nm FET 3.3 SRPD 6 15) SRPD 6 SRPD 1 % 16) 7 15) % 300 mm3 mm % %1 SRPD PD 14) ) PD SRPD SRPD Dose and within-wafer uniformity on R s as function of time with SRPD process SRPD Typical distribution map of R s obtained in process window with SRPD process

5 8 SRPDspike RTARapid Thermal AnnealingSIMS 15) SRPD X j -R s X j R s R s X j 15) spike RTA 8990 SRPD 8as doped SRPD spike RTA SRPD SIMS profiles before and after spike RTA process (900 or 990 ) SRPDPD SRPDpMOS FinFETs Schematic of pmos FinFETs SRPDpMOS FinFETs 10aSRPDpMOS FinFETsTEM 15) bb+ 17 nm SRPD 11SRPD 15) SRPD 0.25 kv 9SRPDFET 9 SRPD asprdbb+pmos FINFETsTEM TEM image of 17 nm width/63 nm height fin fabricated with (a) SRPD and (b) B+ ion implant reference, respectively

6 SRPDPD PD FET LSI FET SRPDB+pMOS FinFETs V TSAT -rolloff V TSAT -rolloff characteristics of nm gate length FinFETs 1Noyce, R. N. : U.S. Patent 2,981,877, filed July 30, Hoerni, L. A. : U.S. Patent 3,025,589 and 3,064,167, filed May1, : IC50IC pp (2008) pp N. Collaert, et al. : Integration challenges for multi-gate devices. Proc. of ICICT p.187 (2005). 6K. Uejima, et al. : Pushing planar bulk CMOSFET scaling to its limit by ultimately shallow diffusion-less junction. IEDM Tech. Dig. pp (2007). 7D. Lenoble, et al. : Enhanced performance of PMOS MUGFET via integration of conformal plasma-doped source/drain extensions. Symp. on VLSI Tech. Dig. pp (2006). 8H. Kawasaki, et al. : Demonstration of highly scaled FinFET SRAM cells with high-k/metal gate and investigation of characteristic variability for the 32 nm node and beyond. IEDM Tech. Dig. p.237 (2008). 9Y. Sasaki, et al. : B 2 H 6 plasma doping with "In-situ He preamorphization". Symp. on VLSI Tech. Dig. pp (2004). 10Y. Sasaki, et al. : New method of plasma doping with in-situ helium pre-amorphization. Nucl. Instr. and Meth. in Phys. Res. B 237,pp (2005). 11Y. Sasaki, et al. : Production-worthy USJ formation by selfregulatory plasma doping method. Proc. of 15th IIT, pp (2006). 12B. Dumont, et al. : Plasma doping for S/D extension: Device integration, gate oxide reliability and circuit demonstration. Proc. of ESSDERC, pp (2005). 13W. Vandervorst, et al. : Conformal doping of FINFETs: a fabrication and metrology challenge. Proc. of 17th IIT, p.449 (2008). 14D. Lenoble, et al. : Advanced junction fabrication challenges at the 45nm node. SEMICONDUCTOR FABTECH-30 th EDITION, pp (2006). 15Y. Sasaki, et al. : Conformal doping for FinFETs and precise controllable shallow doping for planar FET manufacturing by a novel B 2 H 6 /helium self-regulatory plasma doping process. IEDM Tech. Dig. p.917 (2008). 16Y. Sasaki, et al. : U. S. Patent filed Apr Ultimate Junction Technologies Inc. Ultimate Junction Technologies Inc. Ultimate Junction Technologies Inc URLhttp://psuf.panasonic.co.jp/ujt/company/