氩气对直流弧光放电PCVD金刚石薄膜晶体特征的影响

Effect of Argon Gas on the Crystal Feature of Diamond Films Deposited by Direct Current Arc Discharge PCVD Method

本文采用自主研制的直流弧光放电等离子体CVD设备,在YG6硬质合金基体上进行了不同氩气流量下金刚石薄膜的制备研究。采用SEM对金刚石薄膜的晶体特征进行了观察。结果表明,氩气对直流弧光放电等离子体CVD金刚石薄膜的晶体特征有明显影响。在CH4/H2恒定时(0.8%),硬质合金基体上制备的金刚石薄膜表面形貌随Ar流量增加而变化的规律,即从以(111)八面体晶面为主→(111)和(100)立方八面体混杂晶面→以(100)立方体晶面为主→菜花状的顺序转变;当Ar流量为420～700mL/min时,金刚石晶粒的平均尺寸由1.5μm逐步增大到7μm;Ar流量为700～910mL/min时,金刚石晶粒的平均尺寸由7μm急剧减小到纳米尺度,约50nm。

Diamond films have been deposited on an abraded cemented carbide tungsten tool by DC arc discharge plasma CVD under different argon gas flow.The crystal feature of synthesized diamond films was characterized by scanning electron microscopy.The results indicated that the Ar gas has evident effect on the crystal feature of the direct current arc discharge PCVD diamond film.It showed that as argon gas flow increasing,CH4/H2=0.8%,the surface morphology of the diamond films would be changed from （111） crystal face of octahedron → （111）＋ （100） crystal face of cub-octahedron → （100） crystal face of cube→cauliflower type.As the argon gas flow increased from 420 to 700 mL/min,the average size of the diamond grain gradually increased from 1.5 μm to 7 μm,and when from 700 to 910 mL/min,the average size sharply decreased from 7 μm to 50 nm.