Study of sigma-shaped source/drain recesses for embedded-SiGe pMOSFETs

• In this paper, the manufacturing process and formation mechanism study of sigma-shaped source/drain (S/D) recess in 28 nm node pMOSFETs and beyond have been presented. The mechanism of forming sigma-shaped recesses included a detailed analysis how to apply the dry and wet etching to shape the recess in a controlled way. The key factors in etching parameters were identified and optimized. Simulations of strain distributions in the channel region of the devices with selectively grown Si0.65Ge0.35 on different S/D recess shapes were carried out and the results were used as feedback to find out a trade-off between maximum strain in the channel region of the transistors and low short channel effect. Finally, guidelines for designing the shape of recess and for tuning the etching parameters for high mobility transistors have been proposed.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Annan teknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Other Engineering and Technologies (hsv//eng)

Keyword

Dry etching

MOSFET devices

Strain

Publication and Content Type

ref (subject category)

art (subject category)