目前激光直写膜电阻时，所加入的辅料容易造成杂质污染，膜的厚度和粗糙度难以降低。为减少杂质污染，降低膜厚和表面粗糙度，改善激光直写微电路性能，进行了透射式激光直写金属薄膜电阻的实验研究，分析了薄膜线宽与激光光斑能量分布特点的关系，获得了线宽低于光斑直径的导电薄膜。实验表明，扫描速度的增加或离焦量的降低会导致光斑重叠率和导线宽度减小。同时，过高的功率会使薄膜受到烧蚀破坏，功率过低则难以将靶材充分熔化附着在玻璃基板上。相比之下，锌膜颗粒尺寸较为均匀，而Al /Zn混合膜的颗粒尺寸不一致。

When thin film resistors are directly written by laser, auxiliary material can cause impurity pollution. Thickness and roughness of the film cannot be reduced easily. To reduce impurity pollution, film thickness, roughness and improve the performance of microcircuit directly written by laser, the research of metallic film resistors directly written by transmissive laser is carried out. The characteristic relation of laser spot energy distribution and film line width is analyzed. The conductive film of line width less than spot dimension can be obtained. The experimental results show that the increase of scanning speed or the decrease of defocusing amount can lead to the decline of overlapping cofficient of spot and line width decline. Meanwhile, excessively high laser power can lead to abliative damage to thin film; excessively low laser power cannot melt the powder on the glass substrate. With different powders in the process, it is known that Zn powder can form a uniform thin film while Al /Zn powder cannot form a uniform thin film.