干法刻蚀中晶圆表面温度控制研究

Research on Temperature Control of Wafer Surface in Dry Etching

干法刻蚀工艺中,晶圆温度会直接影响刻蚀速率、刻蚀均匀性及刻蚀形貌,从而对最终的器件性能产生影响。对干法刻蚀过程中会对晶圆温度产生影响的若干因素进行了研究,并通过实验确认了不同因素对晶圆温度的影响趋势及范围,为工程应用提供一定参考。通过实验,确认了静电吸盘的夹持电压及氦压、射频源功率、下电极温度及晶圆本身都会对刻蚀过程中的晶圆温度产生一定影响,其中静电吸盘的夹持电压及氦压对晶圆温度影响最大,晶圆翘曲、下射频源功率次之,上射频源功率、下电极冷却温度对晶圆温度影响基本相当,影响程度最小。

In dry etching process,temperature of wafer surface will directly affect etch rate,etch uniformity and etch profile,thus affecting final device performance.Therefore,temperature control of wafer surface is very important in dry etching process.In this paper,several factors affecting wafer temperature during dry etching are studied,and the influence trend and range of different factors on wafer temperature are confirmed through experiments,which provides some references for engineering applications.Through experiments,the clamping voltage and helium pressure of ESC are confirmed.The power of RF source,the temperature of the lower electrode and the warping of the wafer all have certain influence on wafer temperature during etching process.The holding voltage and helium pressure of ESC have the greatest influence on wafer temperature,followed by the power of RF source.The power of ICP source,the cooling temperature of the lower electrode and the warping of the wafer have the same influence on wafer temperature,and the influence degree is the least.