Relation between etching profile and voltage-current shape of sintered SiC etching by atmospheric pressure plasma

(整期优先)网络出版时间:2019-04-14
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Sinteredsiliconcarbide(SiC)wasetchedbyadielectricbarrierdischargesource.Ahighvoltagebipolarpulsewasusedwithheliumgasfortheplasmageneration.OnestablefilamentplasmawasgeneratedandcouldbeusedforSiCetching.Astheprocessinggas(NF3)mixingrateincreased,thewidthanddepthoftheetchingprofilebecamenarroweranddeeper.ThedifferentiatedV-QLissajousmethodwasusedformeasuringthecapacitances(Ceq)oftheelectrodeaftertheplasmaturnedon.ThewidthoftheetchingprofilewasproportionaltoCeq.Asthecurrentpeakvalue/smxofthesubstratecurrentincreased,thevolumeremovalrateofSiCincreased.Theetchdepthwasproportionaltotheratioof/smxtoCeq.Additionally,becauseofthedifferentcharacteristicsoftheplasmadisksonSiCsubstratebythevoltagepolarity,theetchingprofilewasunstable.However,inhighNF3mixingprocess,theetchingprofilebecamestableanddeeper.