射频磁控溅射CN_x薄膜的结构与衬底温度关系的研究

Studies on the Relationship Between Substrate Temperature and Structure of CN_x Thin Films Deposited by R.F. Magnetron Sputtering

使用射频磁控溅射方法在不同衬底温度下 ( ts=室温 ,35 0 ,5 0 0℃ )于 Si( 0 0 1 )衬底上沉积了 CNx 膜 ,并利用拉曼 ( Raman)光谱、傅里叶变换红外光谱 ( FTIR)及 X射线衍射光电子能谱 ( XPS)对 CNx 膜的化学结合状态与温度的关系进行了研究 .Raman光谱结果表明 ,随衬底温度 ( ts)增加 ,D带向低频方向移动 ,G带向高频方向移动 ;它们的半高宽分别由 375和 1 5 0 cm- 1减小至 32 8和 1 4 2 cm- 1 ;ID/IG 由 3.76减小至 2 .88.FTIR谱中除无序 D带 ( 1 4 0 0 cm- 1 )和石墨 G带 ( 1 5 70 cm- 1 )外 ,还有～ 70 0 cm- 1 ,～ 2 2 1 0 cm- 1 ( C≡ N) ,2 330 cm- 1 ( C—O)及 3 2 5 5～ 335 1 cm- 1 ( N—H)等峰 .XPS测试结果表明 :随衬底温度增加 ,N与 C的物质的量比由 0 .4 9下降至 0 .38,sp2 ( C—N)组分与 sp3( C—N)组分强度比呈增大趋势 .低温 ( 35 0℃ )退火并未对CNx 膜的化学结合状态产生较大影响 ;高温 ( 90 0℃ )

CN x thin films were synthesized on Si(001) at different substrate temperatures( t s=room temperature, 350, 500 ℃) by R.F. magnetron sputtering method, Raman spectroscopy, FTIR spectroscopy and XPS were used to study the relationship between the chemical binding state of CN x thin films and temperature. Raman spectra shows that with the increase of t s, D band position shifted towards a lower frequency, while G band position shifted towards a higher frequency. Their full width at half maximum decreased from 375 and 150 cm -1 to 328 and 142 cm -1 respectively, and the ratio of I D/I G decreased from 3 76 to 2 88 too. Except for disorder D band(1 400 cm -1 ) and graphitic G band(1 570 cm -1 ), ca . 700, ca . 2 210(C≡N), 2 330(C-O) and 3 255-3 351 cm -1 (N-H) appeared in FTIR spectra. From XPS spectra we can conclude that with the rise of t s, mol ratio of N/C decreased from 0 49 to 0 38, while the compound ratio of sp 2(C-N) to sp 3(C-N) had a trend of increasing. Lower annealing temperature(350 ℃) had no significant effects on the chemical binding state of CN x thin film, but higher annealing temperature(900 ℃) led to the better crystallization degree of the sample.