Do-Sun Lee

Bulk planar 20nm high-k/metal gate CMOS technology platform for low power and high performance applications

A 20 nm logic device technology for low power and high performance application is presented with the smallest contacted-poly pitch (CPP) of minimal 80 nm ever reported in bulk Si planar device. We have achieved nFET and pFET drive currents of 770 µA/µm and 756 µA/µm respectively at 0.9 V and 1 nA/µm Ioff with the novel high-k/metal (HKMG) gate stack and advanced strain engineering. Short channel effect is successfully suppressed thanks to the optimized shallow junction, resulting in excellent DIBL and subthreshold swing below 120 mV and 90 mV/dec, respectively. In addition, full functionality of SRAM device with 20 nm technology architecture is confirmed.

Fin-channel-array transistor (FCAT) featuring sub-70nm low power and high performance DRAM

For the first time, a highly manufacturable fin-channel array transistor (FCAT) on a bulk Si substrate has been successfully integrated in a 512 M density DRAM with sub-70nm technology. The FCAT shows an excellent short channel behavior, such as extremely low subthreshold swing (SS) (/spl sim/75mV/dec) and DIBL (/spl sim/13mV/V), and a high cell transistor drive current with remarkably low subthreshold leakage current (/spl sim/0.2fA/cell).

Annealing process and structural considerations in controlling extrusion-type defects Cu TSV

Stresses induced by the large volume of Cu in Through Silicon Vias (TSV) can result in global/local Cu extrusion which may affect reliability in 3D chip stacking technologies beyond the 28 nm node for high performance mobile devices. In this work, TSV structural factors that can influence extrusion post via filling are studied. In addition, the impact of the electroplating chemistry and annealing schemes on local extrusion type defect formation in TSVs are also studied.

Highly reliable Cu interconnect strategy for 10nm node logic technology and beyond

CVD-Ru represents a critically important class of materials for BEOL interconnects that provides Cu reflow capability. The results reported here include superior gap-fill performance, a solution for plausible integration issues, and robust EM / TDDB properties of CVD-Ru / Cu reflow scheme, by iterative optimization of process parameters, understanding of associated Cu void generation mechanism, and reliability failure analysis, thereby demonstrating SRAM operation at 10 nm node logic device and suggesting its use for future BEOL interconnect scheme.

Superior Cu fill with highly reliable Cu/ULK integration for 10nm node and beyond

It is possible to overcome Cu void issues beyond 10nm node device by adapting CVD-Ru liner instead of conventional PVD Ta liner. However, CVD Ru liner integration degrades TDDB performance without optimizing its scheme. In this paper, superior gap-fill performance without TDDB performance degradation will be described in our optimized integration scheme along with a proposal for the mechanism of TDDB degradation in the Ru integration scheme. CVD-Ru liner is the prime candidate for Cu metallization at 10nm node and beyond.