Time resolved measurement of film growth during reactive high power pulsed magnetron sputtering (HIPIMS) of titanium nitride

摘要

The growth rate during reactive high power pulsed magnetron sputtering(HIPIMS) of titanium nitride is measured with a temporal resolution of up to 25us using a rotating shutter concept. According to that concept a 200 um slit isrotated in front of the substrate synchronous with the HIPIMS pulses. Thereby,the growth flux is laterally distributed over the substrate. By measuring theresulting deposition profile with profilometry and with x-ray photoelectronspectroscopy, the temporal variation of the titanium and nitrogen growth fluxper pulse is deduced. The analysis reveals that film growth occurs mainlyduring a HIPIMS pulse, with the growth rate following the HIPIMS phasesignition, current rise, gas rarefaction, plateau and afterglow. The growthfluxes of titanium and nitrogen follow slightly different behaviors withtitanium dominating at the beginning of the HIPIMS pulse and nitrogen at theend of the pulse. This is explained by the gas rarefaction effect resulting ina dense initial metal plasma and metal films which are subsequently beingnitrified.