SSL Seminar Series 2003 No.2

Combined talks (two speakers)

Date: July 21, 2003
Time: 4:30-5:30pm
Venue: Physics Resource Room (Blk S13 # 02-16)

Speaker I: Mr. Ong Kuang Kian, Clark(Master Candidate of NTU)
Pulsed Laser Annealing for the Formation of Ultra-Shallow p+/n Junctions
The continuous scaling down of gate dimension of ultra-large scale integrated (ULSI) devices for the improvements in performance and speed has aggravated the short channel effects (SCE), which cause excessive leakage to the devices. As a result, the need for ultra-shallow and highly activated junctions becomes more critical especially in sub-0.1 m devices.
The work pertains to the formation of ultra-shallow p+/n junction using ultra-low energy (ULE) implantation and pulsed laser annealing. Ultra-shallow p+/n junctions formed by laser annealing with shallow and deep preamorphization implantation (PAI) were compared. Laser annealing of crystalline Si, without PAI, is demonstrated to form junctions with comparable junction depth and abruptness as formed with PAI. Effect of multiple-pulse laser annealing on dopant redistribution is also investigated. Feasibility of non-melt laser annealing to form ultra-shallow junctions is briefly discussed.

Speaker II: Mr. Sun Yiyang (PhD Candidate)
Structures of high-index metal surfaces studied by LEED and DFT
High-index (or open, vicinal, stepped) transition metal surfaces are of practical interest in areas such as heterogeneous catalysis. Structures of these surfaces are usually the starting points for further studies on electronic, vibrational, energetic and magnetic properties, such as density of states, surface phonon, work function and spin magnetic moment. In this presentation, the Cu(210) surface will be taken as an example to introduce the methodology of surface structure determination, mainly quantitative low energy electron diffraction (LEED) analysis and pseudopotential density functional theory (DFT) calculations.
General trend for multilayer relaxations on open metal surfaces will also be discussed.