當半導體製程技術邁入深次微米的階段，銅因具有較優異之導電性和電致遷移阻抗性而取代了鋁金屬製程。因為銅原子容易擴散至矽基材而造成元件的失效。因此必須於銅矽間導入一層擴散阻障層，以阻止銅和矽的相互擴散。實驗中嘗試利用直流反應磁控濺鍍法沈積ZrAlN薄膜，並探討製程參數對薄膜成份、微結構、電性及阻障性質的影響。

　　實驗結果發現ZrAlN薄膜為ZrN的NaCl結構。薄膜中部分的Zr原子會被Al原子取代，使得ZrAlN薄膜晶格常數比ZrN還要小。隨著氮氣流量增加，薄膜的晶粒尺寸減小。當氮氣流量大於5sccm，薄膜已轉變為非晶質結構。此非晶質化的趨勢，使得薄膜電阻率隨氮氣流量之增加而急遽升高。隨著基板偏壓的施加，ZrAlN薄膜會傾向於更散亂排列的結晶結構，此現象主要是與高能量離子轟擊下薄膜成長選擇之原則有關。此外，高能量離子轟擊亦會使得薄膜之晶粒尺寸變小。當基板偏壓為-75V時，薄膜有最低之電阻率為113.8 μΩ-cm。

　　實驗中並以最佳參數(氮氣流量：2ccm、基板偏壓：-60V)濺鍍之ZrAlN薄膜為擴散阻障層，探討不同熱處理溫度下ZrAlN薄膜於銅矽間的阻擴散性質。由XRD、片電阻、SEM及AES縱深元素分析之結果顯示，在800℃熱處理30分鐘後，ZrAlN薄膜仍能有效阻止銅矽之間的擴散反應發生。

　　As semiconductor device technology approached the deep sub-micron process requirements, copper has replaced aluminum in the interconnect metallization due to its good electrical conductivity and excellent resistance of electromigration. However, Cu-silicide compounds would be easily formed through the reaction between copper and silicon. Therefore, it is necessary to introduce a diffusion barrier between Cu and Si for preventing the inter-diffusion of copper and silicon. In this study, ZrAlN films were grown onto Si(100) by d. c. reactive magnetron sputtering. The effects of process parameters on the composition, microstructure, electrical property and barrier performance of films have been investigated.
　　Experimental results showed that the crystal structure of ZrAlN films is NaCl type and the lattice constant of ZrAlN films was smaller than that of ZrN. The reduction of average lattice constant was induced by partially substituting Zr with Al. The grain size of films decreased with the increasing nitrogen flow rate. As nitrogen flow rate was larger than 5sccm, the microstructure of the film became amorphous and resulted with the rapid increase of resistivity.
　　The preferred orientation of ZrAlN films gradually developed toward (200) plane with the increasing of substrate bias. It is associated with the evolution selection of the film growth under high energy ion bombardment. In addition, high energy ion bombardment also decreased the grain size of films. When substrate bias was equal to -75V, the lowest resistivity of 113.8 μΩ-cm was obtained.
　　The barrier property of ZrAlN films between Cu and Si annealed at various temperatures has also been studied. Results of X-ray diffraction analysis, sheet resistance measurement, scanning electron microscopy and Auger electron spectroscopy all indicated the absence of inter-diffusion within Cu / ZrAlN(bias: -60V) / Si samples, annealed at 800℃ in vacuum for 30 minutes.

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