Title |
Influence of DCS Post flow on the Properties of textrm{WSi}_{x} Thin films |
Keywords |
Dichlorosiliane (DCS, SiH_2Cl_2) ; Tungsten Silicide ( textrm{WSi}_{x}) ; Sheet Resistance ; Film stress ; Contact Resistance |
Abstract |
In this paper, we studied the physical and electrical characteristics of textrm{WSi}_{x} thin film with respect to the adoption of the DCS (dichlorosiliane) post flow and the variation of deposition temperature. XRD measurements show that as deposited thin film has a hexagonal structure regardless of deposition Process. However, we find that the phase of thin film has changed to a tetragonal structure after the heat treatment at 680°C. Adoption of DCS post flow and increment of deposition temperature result in the increments of Si/W composition ratio. These conditions also result in the increment of sheet resistance by the amount 3.0~4.2Ω/ square, but give the tendency in the decrement of stress by 0.27~0.3 E10dyne/ textrm cm^2. We also find that the contact resistance of word line and bit line interconnection was decreased by the amount 5.33~16.43μΩ- textrm cm^2, when applying DCS post flow and increasing deposition temperature. |