Interface Structures and Electrical Properties of W/Si Films Grown by LPCVD

Authors: Yusuf ATICI, M. Eyüphan YAKINCI, Bülent ULUĞ, Yıldırım AYDOĞDU

Abstract: Interface structures of W films on Si(100) substrates grown by LPCVD from a mixture of WF_{6}, H_{2} and SiH_{4} (silane) gases at 280 ^{\circ}C have been studied by transmission electron microscopy. Cross-sectional and plan-view samples were prepared to characterize the films. Consequently, according to the growth conditions, it has been observed that the W-Si interfaces are rough on a fine scale with some more extensive W protrusions in one of the samples which had an extended initial exposure to WF_{6}. The W films have exhibited many randomly oriented grains ranging between 1000 and 4500 \AA in size. Sheet resistance measurements have also been evaluated by means of four-point contact method at low temperatures (47-300 K) and it has been detected that the sheet resistance of a film decreases as the temperature decreases.

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