物理学报
物理學報
물이학보
2013年
5期
361-368
,共8页
胡明%刘青林%贾丁立%李明达
鬍明%劉青林%賈丁立%李明達
호명%류청림%가정립%리명체
有序多孔硅%氧化钨薄膜%二氧化氮%室温气敏性能
有序多孔硅%氧化鎢薄膜%二氧化氮%室溫氣敏性能
유서다공규%양화오박막%이양화담%실온기민성능
ordered porous silicon%tungsten oxide thin films%nitrogen dioxide%gas-sensing properties at room temperature
利用电化学腐蚀方法制备了n型有序多孔硅,并以此为基底用直流磁控溅射法在其表面溅射不同厚度的氧化钨薄膜.利用X射线和扫描电子显微镜表征了材料的成分和结构,结果表明,多孔硅的孔呈柱形有序分布,溅射10 min的WO3薄膜是多晶结构,比较松散地覆盖在整个多孔硅的表面.分别测试了多孔硅和多孔硅基氧化钨在室温条件下对二氧化氮的气敏性能,结果表明,相对于多孔硅,多孔硅基氧化钨薄膜对二氧化氮的气敏性能显著提高.对多孔硅基氧化钨复合结构的气敏机理分析认为,多孔硅和氧化钨薄膜复合形成的异质结对良好的气敏性能起到主要作用,氧化钨薄膜表面出现了反型层引起了气敏响应时电阻的异常变化.
利用電化學腐蝕方法製備瞭n型有序多孔硅,併以此為基底用直流磁控濺射法在其錶麵濺射不同厚度的氧化鎢薄膜.利用X射線和掃描電子顯微鏡錶徵瞭材料的成分和結構,結果錶明,多孔硅的孔呈柱形有序分佈,濺射10 min的WO3薄膜是多晶結構,比較鬆散地覆蓋在整箇多孔硅的錶麵.分彆測試瞭多孔硅和多孔硅基氧化鎢在室溫條件下對二氧化氮的氣敏性能,結果錶明,相對于多孔硅,多孔硅基氧化鎢薄膜對二氧化氮的氣敏性能顯著提高.對多孔硅基氧化鎢複閤結構的氣敏機理分析認為,多孔硅和氧化鎢薄膜複閤形成的異質結對良好的氣敏性能起到主要作用,氧化鎢薄膜錶麵齣現瞭反型層引起瞭氣敏響應時電阻的異常變化.
이용전화학부식방법제비료n형유서다공규,병이차위기저용직류자공천사법재기표면천사불동후도적양화오박막.이용X사선화소묘전자현미경표정료재료적성분화결구,결과표명,다공규적공정주형유서분포,천사10 min적WO3박막시다정결구,비교송산지복개재정개다공규적표면.분별측시료다공규화다공규기양화오재실온조건하대이양화담적기민성능,결과표명,상대우다공규,다공규기양화오박막대이양화담적기민성능현저제고.대다공규기양화오복합결구적기민궤리분석인위,다공규화양화오박막복합형성적이질결대량호적기민성능기도주요작용,양화오박막표면출현료반형층인기료기민향응시전조적이상변화.
n-type porous silicons are prepared by the electrochemical corrosion method, on which tungsten oxide thin films with different thickness values are sputtered using DC reactive magnetron sputtering. The structures of ordered porous silicons and tungsten oxide thin films are characterized using field emission scanning electron microscope, which show that the pores are pillared and ordered and the thin films cover the porous layer loosely with many pores open to ambient air. The X-ray diffraction characterization indicates that the lattice structure of tungsten oxide thin film is mainly triclinic polycrystalline. The gas-sensing properties at room temperature for both ordered porous silicon and composite structure are studied, which indicate that the latter is much more sensitive to nitrogen dioxide than the former. And there is a critical spurting time of WO3 thin film, which in our case is 10 min. The sensing mechanism of composite structure is discussed and the probable explanation for the improvement of sensitivity to NO2 is the formation of hetero-junctions between the ordered porous silicon layer and the WO3 thin film. In addition, there exists an inversion layer on the surface of the WO3 thin film, which causes the anomalous resistance to change during the gas sensing measurements.