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We have fabricated and demonstrated a new device called the Vertical Replacement-Gate (VRG) MOSFET. This is the first MOSFET ever built that combines (1) a gate length controlled precisely through a deposited film thickness, independently of lithography and etch, and (2) a high-quality gate oxide grown on a single-crystal Si channel. In addition to this unique combination, the VRG-MOSFET includes a self-aligned S/D formed by solid source diffusion (SSD) and small parasitic overlap, junction, and S/D capacitances. The drive current per /spl mu/m of coded width is significantly higher than that of advanced planar MOSFETs because each rectangular device pillar (with a thickness of minimum lithographic dimension) contains two MOSFETs driving in parallel. All of this is achieved using current manufacturing methods, materials, and tools, and competitive devices with 50-nm gate lengths (L/sub G/) have been demonstrated without advanced lithography.

Reports measurements of the DC characteristics of sub-100 nm nMOSFETs that employ low leakage ultra-thin gate oxides only 1-2 nm thick to achieve high current drive capability and transconductance. We demonstrate that I/sub Dsat//spl ap/1.8 mA//spl mu/m can be achieved with a 60 nm gate at 1.5 V using a 1.3-1.4 nm gate oxide with a gate leakage current less than 20 nA//spl mu/m/sup 2/. Furthermore, we find that I/sub Dsat/ deteriorates for gate oxides thicker or thinner than this.

We present the first p-channel Vertical Replacement-Gate (VRG) MOSFETs. Like the VRG-nMOSFETs demonstrated last year, these devices show promise as a successor to planar MOSFETs for highly-scaled ULSI. Our pMOSFETs retain the key features of the nMOSFETs and add channel doping by ion implantation and raised source/drain extensions (SDEs). We have significantly improved the core VRG process to provide high-performance devices with gate lengths of 100 nm and below. Since both sides of the device pillar drive in parallel, the drive current per /spl mu/m of coded width can far exceed that of planar MOSFETs. Our 100 nm VRG-pMOSFETs with t/sub ox/=25 /spl Aring/ drive 615 /spl mu/A//spl mu/m at 1.5 V with I/sub OFF/=8 nA//spl mu/m-80% more drive than specified in the 1999 ITRS Roadmap at the same I/sub OFF/. We demonstrate 50 nm VRG-pMOSFETs with t/sub ox/=25 /spl Aring/ that approach the 1.0 V roadmap target of I/sub ON/=350 /spl mu/A//spl mu/m at I/sub OFF/=20 nA//spl mu/m without the need for a hyperthin (

We have integrated HfO/sub 2/ and Al/sub 2/O/sub 3/ gate dielectrics grown by atomic layer chemical vapor deposition (ALD) with poly-Si gate electrodes in the vertical replacement-gate (VRG) MOSFET geometry. These transistors are among the first reported with ALD HfO/sub 2/ gate dielectrics, and have HfO/sub 2/ target equivalent oxide thicknesses (tEOT's) down to 13 /spl Aring/. The poly-crystalline HfO/sub 2/ films in these VRG nMOSFETs exhibit extremely low gate leakage (GL) current densities of J/sub G/ /spl sim/ 10/sup -7/ A/cm/sup 2/ at V/sub G/-V/sub T,Long/ = 0.6 V for 15 /spl Aring/ tEOT devices. This indicates that amorphous gate dielectrics may not be necessary to meet GL requirements. HfO/sub 2/ devices with 50 nm gate length L/sub G/ exhibit drive currents [normalized by the coded width W/sub C/] of 490 /spl mu/A//spl mu/m for 1 V operation (overdrive V/sub GS/-V/sub T/ = 0.6 V) with good short-channel performance. These results demonstrate that ALD is compatible with the demanding VRG geometry, thereby illustrating that it should be well-suited to essentially any novel device structure built with Si-compatible materials.