Paul A. Grudowski

1-D and 2-D Geometry Effects in Uniaxially-Strained Dual Etch Stop Layer Stressor Integrations

We report, for the first time, on the 2D boundary effects in a high performance 65nm SOI technology with dual etch stop layer (dESL) stressors. 1D geometry effects, such as poly pitch dependence, and the implications on SPICE models and circuit design are also discussed. It will be shown that PMOS and ring oscillator performance can be significantly enhanced by optimizing the transverse and lateral placement of the dESL boundary

Embedded SiGe S/D PMOS on thin body SOI substrate with drive current enhancement

We report for the first time PMOS drive current enhancement with in-situ boron doped SiGe incorporation in recessed S/D regions for devices built on thin body SOI substrate. For P-channel PD-SOI devices with 450 A silicon on insulator and 38nm gate length, 35% linear drain current enhancement and 20% saturation drain current improvement have been achieved with this approach. Device integration and performance improvement are discussed below.

Strain-Enhanced CMOS Through Novel Process-Substrate Stress Hybridization of Super-Critically Thick Strained Silicon Directly on Insulator (SC-SSOI)

This paper describes a biaxial-uniaxial hybridized strained CMOS technology achieved through selective uniaxial relaxation of thick SSOI, dual-stress nitride capping layer, and embedded SiGe source/drain. Through novel strain engineering, nFET/pFET Idsat enhancements as high as 27%/36% have been achieved for sub-40nm devices at 1V with 30% reduction in gate leakage current, while introducing minimum process complexity. This work demonstrates the scalability of SC-SSOI and its advantages over pure biaxial and single uniaxial strained Si technologies

Multi-Layer Model for Stressor Film Deposition

Multi-layer simulation is proposed for accurate modeling of stressor film deposition. Multi-layer simulation subdivides a single deposition into a series of deposition and relaxation steps to emulate mechanical quasi-equilibrium during the physical deposition process. Only the multi-layer model is able to simultaneously match the experimental data on drive current vs. etch-stop layer stress, poly pitch, source/drain recess, and spacer stress

An Embedded Silicon-Carbon S/D Stressor CMOS Integration on SOI with Enhanced Carbon Incorporation by Laser Spike Annealing

We report a CMOS-compatible embedded silicon-carbon (eSiC) source/drain stressor technology with NMOS performance enhancement. The integration includes up to 2.6% substitutional carbon (Csub) epitaxial Si:C and laser spike annealing (LSA) for increased Csub incorporation. 26% channel resistance (Rch) reduction and 11% Idlin-Ioff enhancement for 0.5% Csub and 60% Rch reduction for 2.2% Csub are demonstrated.

Optimization of Dual-ESL Stressor Geometry Effects for High Performance 65nm SOI Transistors

We report on the optimized transverse and lateral boundaries of dual etch stop layer (dESL) stressors in both PMOS and NMOS achieved in 65nm SOI transistors. We demonstrate that this gives an additional ~20% performance gain in ring oscillators. The optimization takes into account the 1-D and 2-D geometry effects, including poly-pitch, and is in good agreement with stress simulations

Dual Silicide SOI CMOS Integration with Low-Resistance PtSi PMOS Contacts

We demonstrate a dual silicide integration on a SOI CMOS platform with robust low-resistance PtSi PMOS contacts. Compared to NiSi, the specific contact resistivity is reduced in PtSi contacts to p-type Si and increased in contacts to n-type Si. PMOS linear and saturation drive current enhancements of 6% and 9%, respectively, were achieved with PtSi relative to baseline NiSi source/drain contacts.

Uniaxial and Biaxial Strain for CMOS Performance Enhancement

Uniaxial stressors have been mainly employed for boosting PMOS performance, while it is more difficult to increase NMOS performance using tensile stressors. This results in changing the n:p ratio, which requires circuit layout changes. Enhancing both NMOS and PMOS performance to retain the same n:p ratio is desirable. Interactions between biaxial lattice strain, uniaxial relaxation, process-induced stressor and channel orientation have been optimized to achieve the desired stress configurations for enhancing both short-channel SSOI NMOS and PMOS devices

Performance Enhancement via Laser Anneal-Based RS/D Reduction in PD/SOICMOS

Extrinsic source/drain series resistance (RSD/) becomes a limiting factor as performance boosters, such as strain-Si and metal-gate/high-k gate stack that enhance the intrinsic MOSFET, are vigorously pursued and implemented in nanoscale CMOS (Ghani, et al., 2003). Non-melt laser spike anneal (LSA) (Feng et al., 2004) has been suggested (Shima, et al., 2004), (Fung et al., 2004) as a means to reduce RSD/. In this paper, we present, for the first time, application of LSA to 35nm gate length, high-performance PD/SOI CMOS with dual etch stop layer (dESL) stressors and NiSi (Grudowski et al., 2006), showing 10% (4%) nFET (pFET) on-state current (Ion) enhancement and non-self-heated Ion=1520/1160muA/mum (880/630muA/mum) at VDD=1.2V/1.0V

Optimization of annealing process of pulsed RF decoupled plasma nitridation oxynitrides

Optimization of post nitridation annealing (PNA) in plasma nitrided gate oxide integration exhibited reduction of gate leakage current and improvement of negative bias temperature instability (NBTI) without drive current loss have been demonstrated. An improved interface quality by a high temperature or a high pressure O2 PNA is the main factor to improve channel mobility. The addition of both post clean annealing (PCA) and post oxidation annealing (POA) allows for gate dielectric scaling down with the benefit of drive current improvement. An increase in oxide thickness and a decrease in relative nitrogen concentration resulted in the improvement of NBTI characteristics.