介绍了采用CO2激光器对聚甲基丙烯酸甲脂(PMMA)板进行刻蚀制备微流道的工艺实验。通过实验分析工艺参数对微流道深度和宽度的影响及其中变化规律。结果表明，激光线能量密度与刻蚀微流道宽度两者关系呈指数增长，得到了线能量密度和微流道宽度的数学拟合公式，曲线和数据点拟合决定系数R2=0.96。当线能量密度小于300 J/m时，微流道深度与线能量密度呈近似线性关系；当线能量密度大于300 J/m时，偏离线性关系。通过理论计算得到在低线能量密度下微流道深度的变化曲线图，并与实际测量值吻合较好。最后，通过优化工艺参数，制备出微流道宽度为170 μm，深度为180 μm的生物芯片。

A micro-ablation of polymethyl methacrylate (PMMA) is carried out by CO2 laser. The effect of the process parameters on the depth and width of the channel is further studied. The rule of the process parameters how to affect the groove depth and width is obtained by the experimental analysis. The results show that the laser line energy density has an exponential relation with the channel width. Through the experiment, we achieve the experiental formula about the line energy density and groove width and the decisive coefficient R2 is 0.96. When the line energy density is less than 300 J/m, the depth of ablated channel has a linearity relation with the line energy density, but this relation is deviated for the line energy density over 300 J/m. By the law of conservation of energy, a model about the channel depth and line energy density is set up. At the situation of low line energy density less than 300 J/m, the calculated results agree well with the experiment. At last, with optimization of process parameters, we make a fine biochip with width of 170 μm and depth of 180 μm.