(Invited) Advanced (Millisecond) Annealing in Silicon Based Semiconductor Manufacturing

Abstract

Rapid thermal annealing has taken a new turn at the beginning of this century with the advent of term "advanced annealing". Although the annealing techniques are a few decades old, they have not seen many applications in the semiconductor industry until recently, primarily due to the complexity of the tools involved and their mechanical interaction with silicon wafers. The tolerance for dopant diffusion has reduced significantly from one ITRS node to next. Advanced anneals rely primarily on achieving super-high temperatures (>1100oC) in very short periods of time (milliseconds). These anneals provide the relevant thermal budget for dopant activation processes with minimal diffusion, thus making them attractive. However, as process integration has become more complex additional challenges are encountered by super-high temperature anneals at the recent technology nodes. Additionally, these annealing techniques impart severe mechanical stress on wafers by heating the wafers at rates >10^5 oC/s. This paper will focus on simulation and experimental verification of stress that is experienced by silicon wafers during a millisecond annealing process

Combined IV and CV Analysis of Laser Annealed Carbon and Boron Implanted SiGe Epitaxial Layers

“…This large hump in the no-implant sample also indicates that a laser treatment can enhance the defectivity at ~170 nm in the substrate because no hump is observed before the laser annealing. Such a laser enhanced defectivity is also reported in (26).…”

Growth and Processing Defects in CMOS Homo- and Hetero-Epitaxy

“…It emphasizes once more that the main factor in the leakage current are the residual, implantation-induced point defects and point-defect clusters and not so much the strain in the silicon substrate (28). In order to reduce the thermal budget further, flash-lamp or laser annealing (socalled ms annealing -MSA) is becoming more and more popular (29,30). However, the high thermal stresses associated with the strong temperature gradients may result in strain relaxation of the SiGe layer when the laser annealing conditions (dwell time, maximum power) are not properly optimized (16,(31)(32)(33).…”