Buried Cobalt Silicide Layers in Silicon Created by Wafer Bonding

• A buried conductive layer in silicon has been created using wafer bonding technique, with a cobalt interfacial layer.Co-coated silicon wafers were brought into contact with either similar or uncoated wafers at room temperature. CoSi2 wasthen formed through a solid-phase reaction, during an anneal at 700 to 900°C. A 700 Å buried CoSi2-layer, with a resistivityof approximately 21 µ cm, was achieved. Good adhesion, as measured by tensile strength testing, between the wafers wasachieved. Transmission electron microscopic investigations (Co-coated wafer bonded to bare silicon) showed that thesilicide has not grown into the opposite wafer, and that an amorphous layer exists between the silicide and the siliconsurface. The presence of such a layer has been confirmed by electrical characterization.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Keyword

Wafer bonding cobalt disilicide

Electrical engineering, electronics and photonics

Elektroteknik, elektronik och fotonik

Publication and Content Type

ref (subject category)

art (subject category)