微纳电子技术

磁控溅射法制备氮化硅薄膜具有工艺简单、粉尘少等优点，氮化硅薄膜在微电子机械系统(MEMS)领域中可用作腐蚀掩蔽层和力学结构层。以氮化硅为靶材、高纯氮气为反应气体，采用射频磁控溅射法在硅衬底上制备氮化硅薄膜，在射频功率150 W、偏压150 V、工作气压0.5 Pa、温度450℃、氩气体积流量60 cm³/min的条件下，随着氮气体积流量从0增加到25 cm³/min,氮化硅薄膜的沉积速率先增大后减小，薄膜的压应力从1.38 GPa逐渐减小到672.2 MPa。沉积的氮化硅薄膜在质量分数为10%的HF溶液中的腐蚀速率从20.1 nm/min减小到5.9 nm/min,在80℃、质量分数为40%的KOH溶液中的腐蚀速率从26.8 nm/min减小到1.3 nm/min。随着氮气体积流量增加，薄膜更为致密，缺陷减少，可应用于红外光源、流量传感器等MEMS器件中作为绝热层或者钝化层。

The silicon nitride films prepared by magnetron sputtering method with the advantages of simple process and less dust can be used as corrosion mask and mechanical structure layer in the field of micro-electromechanical system(MEMS). With silicon nitride as target material and high-purity nitrogen as reaction gas, silicon nitride films were prepared on silicon substrates by radio frequency magnetron sputtering method. Under the conditions of a RF power of 150 W, a bias voltage of 150 V, a working pressure of 0.5 Pa, a temperature of 450 ℃ and an argon volume flow rate of 60 cm³/min, the deposition rate of silicon nitride films firstly increases and then decreases with the volume flow rate of nitrogen increasing from 0 to 25 cm³/min, and the compressive stress of the films gradually decreases from 1.38 GPa to 672.2 MPa. The corrosion rate of the deposited silicon nitride films decreases from 20.1 nm/min to 5.9 nm/min in HF solution with a mass fraction of 10%, and the corrosion rate decreases from 26.8 nm/min to 1.3 nm/min in KOH solution with a mass fraction of 40% at 80 ℃. With the increase of nitrogen volume flow rate, the films become more compact and have fewer defects, and can be applied as adiabatic layer or passivation layer in MEMS devices such as infrared light sources and flow sensors.