The influence of thermal processing on structural and electrical properties of WxSi1−x/Si multilayers

• Thermal stability of WxSi1−x/Si multilayers (MLs) with x varying from 1 to 0.11 is studied by TEM and LAXS. The structure of the prepared samples is amorphous. Doping of W sublayers with silicon affects the interdiffusion process as well as the crystallization in these sublayers. We investigated these two processes (which have a detrimental influence on e.g. X-ray mirror stability) by annealing our samples at 400°C for 40 min. The structural changes were monitored by resistance measurement in the temperature range of 1.5–300 K. A correlation between structural and electrical characteristics was found, which is based on the comparison between three different R(T) curves. It is shown in our paper that the R(T) curve of a ML lies between the R(T) curves of two extreme types of single layers. The first single layer is the analogue of a fully intermixed ML and the second one represents a parallel connection of all conductive sublayers. Thus, a simple resistance measurement can give additional information about the quality of interfaces. We claim that in MLs with ultrathin sublayers the reported highest thermal stability of the amorphous mixture W0.72Si0.28 cannot be utilized because interdiffusion dominates over crystallization so that the superlattice structure is not retained.

Subject headings

NATURVETENSKAP  -- Kemi -- Oorganisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Inorganic Chemistry (hsv//eng)

NATURVETENSKAP  -- Kemi -- Materialkemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Materials Chemistry (hsv//eng)

Publication and Content Type

art (subject category)

ref (subject category)