氟化非晶碳薄膜(a-C:F)的制备与表征  

Preparation and Characterization of Fluorinated Amorphous Carbon(a-C:F)

作　　者：苏祥林[1] 吴振宇[1] 蒋昱[1] 汪家友[1] 杨银堂[1] 

机构地区：[1]西安电子科技大学微电子所宽禁带半导体材料与器件教育部重点实验室,西安710071

出　　处：《半导体技术》2006年第2期90-93,共4页Semiconductor Technology

基　　金：电子元器件可靠性物理及其应用技术国家级重点实验室资助项目(51433020205DZ0101)

摘　　要：以C4F8和CH4为源气体,采用电子回旋共振等离子体化学汽相沉积(ECR-CVD)方法,在不同气体混合比条件下沉积了非晶氟化碳(a-C:F)薄膜低k层间介质。实验中薄膜的沉积速率可达220nm／min, 测得的介电常数为2．14-2．58。X光电子能谱表明,随着甲烷含量增大,薄膜中CF3,CF2结构含量减少而 CF和C*-CFx(x=1-3)交联结构增多:原子力显微镜表明,在采用C4F8为前驱气体时,高分子基团CxFy 在成膜时造成了粗糙不平、多孔渗水的薄膜表面形貌。结果表明,CF基因成分增加而CF2基团成分减小导致了薄膜电子极化增强,介电常数增大。Fluorinated amorphous carbon（a-C：F） films were deposited using a ECR-CVD reactor with C4F8 and CH4 as the source gases. The a-C：F films can be grown from C4F8/CH4 at high deposition rate（220nm/min） and have low dielectric constant（2.14-2.58）. The X-ray photoelectron spectroscopy analysis shows that as methane gas flow rate increases, the content of CF3,CF2 structures decrease and CF, C^＊ - CFx （x=1 -3）cross-linking structures increase. The atomic force microscopy analysis indicate that the higher-molecular-weight radicals（CxFy） play an important role in the polymerization and lead to a porous polymer in the C4F8 plasma. It is found that an increase in electronic polarization or dielectric constant can be attributed to the increase of CF radical and decrease of CF2 radical in a-C：F films.

关 键 词：电子回旋共振 非晶氟化碳 X光电子能谱 低介电常数 

分 类 号：O484.4[理学—固体物理] TN304.055[理学—物理]