Lateral encroachment of Ni-silicides in the source/drain regions on ultrathin silicon-on-insulator

• Lateral growth of Ni silicide towards the channel region of metal-oxide-semiconductor transistors (MOSFETs) fabricated on ultrathin silicon-on-insulator (SOI) is characterized using SOI wafers with a 20-nm-thick surface Si layer. With a 10-nm-thick Ni film for silicide formation, p-channel MOSFETs displaying ordinary device characteristics with silicided p(+) source/drain regions were demonstrated. No lateral growth of NiSix under gate isolation spacers was found according to electron microscopy. When the Ni film was 20 nm thick, Schottky contact source/drain MOSFETs showing typical ambipolar characteristics were obtained. A severe lateral encroachment of NiSix into the channel region leading to an increased gate leakage was revealed, while no detectable voiding at the silicide front towards the Si channel was observed.

Subject headings

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Keyword

film formation

thin-films

ni2si

diffusion

mosfets

couples

Physics

Fysik

Publication and Content Type

ref (subject category)

art (subject category)