LOW-TEMPERATURE RAPID THERMAL LOW-PRESSURE CHEMICAL-VAPOR-DEPOSITION OF [111] ORIENTED TIN LAYERS FROM THE TICL4-NH3-H-2 GASEOUS-PHASE

Titanium nitride layers are deposited by Rapid Thermal Low-Pressure Ch emical Vapor Deposition (RTLPCVD) from the TiCl4-NH3-H-2 gaseous phase . Growth rate, resistivity and crystallographic orientation are studie d as a function of the deposition temperature and the NH3/TiCl4 partia l pressures ratio called R. To fulfill the TiN barrier layer requireme nts, the deposition temperature and the R value have to be as low as p ossible. We show that with such conditions, the preferential orientati on of the deposited TiN layer is always [200]. This orientation enhanc es the [200] orientation of the aluminium overlayer which leads to poo r electromigration resistance. In order to obtain [111] oriented TiN l ayer, a two step process is proposed. In this way, [111] oriented TIN layers are deposited at a deposition temperature and with an R ratio v alue as low as 500 degrees C and 4, respectively. The resistivity of s uch as-deposited films is 200 mu Omega cm.