Ultra-Shallow Junction Formation by Non-Melt Laser Spike Annealing and its Application to Complementary Metal Oxide Semiconductor Devices in 65-nm Node

Abstract

We activated source/drain junctions of complementary metal oxide semiconductor (CMOS) by simply replacing rapid thermal annealing (RTA) in the conventional production flow by non-melt laser spike annealing (LSA). We did not form any additional layers, unlike the conventional laser annealing. The 50-nm gate CMOS devices thus formed had overwhelmingly better V th roll-offs and larger drain currents compared to those formed by RTA. We found that the LSA-devices without offset spacers had better performance than those with offset spacers, and that the optimization of the overlap length between the gate and source/drain extensions was important due to the minimal lateral diffusion during the sub-millisecond annealing of LSA.

Photothermally Directed Assembly of Block Copolymers

“…Laser spike annealing (LSA) uses a laser beam that has been focused to a short line (e.g., 90 µm × 700 µm) which is scanned over a substrate to induce extreme thermal processing (Figure c). LSA has been used for several years as an alternative processing scheme for semiconductors, where it can control dopant diffusion and strain profiles . Singer et al described the use of focused laser spike (FLaSk) annealing—wherein the incident beam is focused to a spot (e.g., <1 µm in diameter)—for processing of organic thin films.…”

Formation of Ultra-Shallow Junctions

“…LTP or melt laser thermal process (Shima and Hiraiwa, 2006) goes beyond LSA by operating at the nanosecond scale and driving the surface to melt. Using a short high-energy laser pulse of 10-100 ns, a peak temperature in excess of 1400 C is achieved which causes a thin region of the surface to melt.…”

“…With the deployment of flash lamp annealing (FLA) (Ito et al, 2002;Gebel et al, 2002) and laser annealing techniques, which operate on the millisecond time scale, box-like junctions with highly activated dopants can be achieved. The most notable advances of millisecond rapid thermal processing (RTP) techniques are melt and nonmelt laser spike annealing (LSA) (Shima and Hiraiwa, 2006).…”

Laser crystallization for large-area electronics

“…The activation of impurity atoms using rapid annealing technologies is important for the formation of shallow junctions to fabricate a shallow source/drain extension region with a depth of 10 nm in MOS transistor devices for a 45-nm node [46][47][48]. It has not been realized by conventional rapid thermal annealing (RTA).…”