复试有点乱-题目回答

P型半导体，N型半导体，P-N得到N型半导体，多子为电子，少子为空穴，主要靠电子导电。移动的，而电离杂质（离子）N型半导体中有许多可动的负电子和固定的正离子PN型半导体接触时，在界面附近空穴P型半导体N型半导体扩散，电子从N型半导体向P型半导体扩散。空穴和电子相遇而复合，载流子。因此在界面区。P型半导体一边的空间电荷是负离子，N型半导体一边的空间电荷是正离子。正负离子在界面附近产生电场，这电场载流子进一步扩散，达到平衡。PN型半导体接触后，在接触面，NPP型区的多NNP间电荷区。这样，PN结就形成了。三大材料区别（英文Whencomestothewayofinteratomicbonding,metalmaterials'atomsareconnectedbymetallicbonds,non-metallicmaterialshavecovalentbondorionicbondandpolymermaterialshavevanderWaalsbondorcovalentbondIntheaspectsoftheirperformancecharacteristics,metalmaterialsusuallyhavegreattoughnessandplasticity,andareconductive.inanicnon-metallicmaterialsownhighhardnessandareoftencharacterizedasbrittle.Incontract,polymersusuallyhavelowhardness,toughness,good（（材料加工方向缺少样品，可询问老师。Wheninthelackofsomeapparatus,ly,wecanconsiderwhetheritcanbereplacedbyothersinthecaseofhavinglittlenegativeeffectontheresultsoftheexperiment.Ifthereisnosubstituteorneedmoresamples,wecanturntotheteacherwhoisresponsibleforthestuffinlabforhelp.Wecanmakeceramicmugorplasticcup.ceramicCupneedstobepowderedrefining,drying,molding,sintering,secondcuringprocess.ThemethodtomakePlasticcup,isthroughhigh-temperaturematerialsmelt,thenpouringtheliquidintometalmoldparts,cooling,processingforthesecondtime.Thenwegetthefinalproduct.碳--塑料二级复型膜：在样品表面滴一滴，在未完全挥发前贴上一块醋酸纤维塑料层碳，得碳二级复型。将其剪成2nm见方的小方块，在溶液中溶去塑料膜，碳膜漂浮于中，漂洗，展开晒干后即得碳塑料