简介：InordertoaccomplishreliablemechanicaldesignofMEMS,theinfluencesofsurfaceroughnessandoctadecyltrichlorosilane(OTS)self-assembledmonolayers(SAMs)onthemechanicalpropertiesofmicromachinedpolysiliconfilmsforMEMSareinvestigated.Surfaceeffectonthefracturepropertiesofmicromachinedpolysiliconfilmsisevaluatedwithanewmicrotensiletestingmethodusingamagnet-coilforceactuator.Statisticalanalysisofthesurfaceroughnesseffectsonthetensilestrengthpredicatedthesurfaceroughnesscharacterizationofpolysiliconfilmsbeingtestedandthedirectrelationofthemechanicalpropertieswiththesurfaceroughnessfeatures.Thefracturestrengthdecreaseswiththeincreaseofthesurfaceroughness.Theoctadecyltrichlorosilaneself-assembledmonolayerscoatingleadstoanincreaseoftheaveragefracturestrengthupto32.46%.SurfaceroughnessandthehydrophobicpropertiesofspecimenwhencoatedwithOTSfilmsarethetwomainfactorsinfluencingthetensilestrengthofmicromachinedpolysiliconfilmsforMEMS.

简介：AnumericalanalysiswascarriedouttostudythemovingboundaryprobleminthephysicalprocessofpulsedNd-YAGlasersurfacemeltingpriortovaporization.Theenthalpymethodwasappliedtosolvethistwo-phaseaxisymmetricalmehingproblem.Computationalresultsoftemperaturefieldswereobtained,whichprovideusefulinformationtopracticallairtreatmentprocessing.Thevalidityofenthalpymethodinsolvingsuchproblemsispresented.

简介：Solutionstoapiezoelectrichalf-planewithafixedconductorsurfaceelectrodesubjectedtotwogeneralizedsingularities(linedislocationand/orlineforceandfreecharge)arepresented.Coulombforcesactingonthesingularitiesduetotheboundarypolarizationchargesofmediumandtheinductioncharg-esofconductorelectrodeareanalyzedindetail.Theinteractionbetweenthetwosingularitiesisalsoanalyzednumerically.ResultsshowthatCoulombforceswillbecomeimportantasthefreechargeapproachestheboundaryortwosingularitiesmoveclosely.