Sameer H. Jain

45-nm silicon-on-insulator CMOS technology integrating embedded DRAM for high-performance server and ASIC applications

The 45-nm technology, called 12S and developed for IBM POWER7®, is an extremely robust and versatile technology platform that allows for a rich set of features that include embedded dynamic random access memory (DRAM), performance and dense static RAM (SRAM), a trench-based decoupling capacitor, a comprehensive device menu, and a high-performance hierarchical back-end interconnect scheme, all built on a silicon-on-insulator (SOI) substrate. Embedded DRAM was implemented for production in high-performance SOI for the first time and allowed us to leapfrog two generations of conventional SRAM densities. Immersion lithography was also employed for the first time in 45-nm IBM products. Our 45-nm design point represents a judicious leverage of silicon oxynitride dielectrics, scaled device technology, and rich features to yield chip-level performance enhancement of more than 50%, compared with our 65-nm node at comparable or less power. This paper describes the salient features of this technology node, the process architecture, the device design rationale, and the process design interactions.

Modeling gate-pitch scaling impact on stress-induced mobility and external resistance for 20nm-node MOSFETs

The impact of gate-pitch scaling on device internal and external resistance is examined by advanced process and device modeling including distributed contact resistance model, mechanical stress and Monte Carlo (MC)-based stress-dependent mobility model. The contact resistance components and their major parameters in sub-50nm contact regime are analyzed by TCAD and transmission line modeling (TLM). The calibration method for the stress-induced channel mobility and the external resistance is proposed using Ron-Lgate measurements of 32nm-node devices with different gate-pitches. The significant performance degradation due to simple gate-pitch scaling is predicted for 20nm-node technology with sub-100nm gate-pitch.

Exploring MOL design options for a 20nm CMOS technology using TCAD

A mixed-mode simulation framework is presented to study the AC performance of a 20nm bulk CMOS technology with respect to various options for contact design at the middle-of-line design level. These simulations combine the predictive capabilities of a calibrated two-dimensional TCAD model for a MOSFET with three-dimensional simulations for the layout dependent parasitic capacitances to extract the characteristic parameters of a multi-stage ring-oscillator circuit, such as the ring delay, and the effective switching capacitance. Significant performance degradation is predicted comparing the simulation results for a conventional contact design versus a typical 20nm design considering raised source-drain and a contact bar.