Direct Laser Writing (DLW) is a lithography technique for fabricating features in sub-microns dimensions. Major advantages of this technique are the elimination of mask, cost-effectiveness and design scalability. Patterns with different dimensions and geometries can be fabricated using this technique, which are greatly influenced by several laser parameters such as the intensity of the laser, speed of the stage (substrate), and focus level of the laser. To achieve high accuracy, the effects of the operative parameters on width is required to be mapped. In this work, the effect of parameters such as laser intensity, stage speed, and focus level (Z-axis movement) on the features of the micropatterns has been investigated. The laser intensity was varied from 25000 W/m2 to 65000 W/m2, and the stage speed was varied from 20 steps per minute to 200 steps per minute. The focus level was altered from the far limit of the Z-axis and incremented by a value of 0.1 mm. The patterns were created on glass substrates coated with negative dry film photoresist. The geometry of the obtained patterns was analyzed using optical microscopy and scanning electron microscopy. Subsequently, statistical tools were employed to frame empirical relationships of the parameters with feature size as a response function. The construction of the efficient experimental combinations has been performed using design of experiments (DOE) and the response values were analyzed using tools such as Analysis of Means (ANOM) and Analysis of Variance (ANOVA). Except knowing the significance of all the individual parameters, it was observed that the focus level highly influenced the feature size compared to the intensity of laser and stage speed. The applications of these devices in the fields of droplet based microfluidics and interdigitated electrodes for electrochemical sensing have are also been discussed.

中文翻译：

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用于微尺度应用的直接紫外激光写入系统的优化和表征

直接激光写入 (DLW) 是一种用于制造亚微米尺寸特征的光刻技术。这种技术的主要优点是消除了掩模、成本效益和设计可扩展性。使用这种技术可以制造具有不同尺寸和几何形状的图案，这些图案受几个激光参数的影响很大，例如激光强度、平台（基板）的速度和激光的聚焦水平。为了实现高精度，需要映射操作参数对宽度的影响。在这项工作中，研究了诸如激光强度、载物台速度和焦点水平（Z 轴移动）等参数对微图案特征的影响。激光强度从 25000 W/m2 到 65000 W/m2 不等，舞台速度从每分钟 20 步到每分钟 200 步不等。聚焦水平从 Z 轴的远极限改变，并增加了 0.1 毫米的值。这些图案是在涂有负性干膜光刻胶的玻璃基板上创建的。使用光学显微镜和扫描电子显微镜分析获得的图案的几何形状。随后，使用统计工具来构建参数与特征大小作为响应函数的经验关系。使用实验设计 (DOE) 构建了有效的实验组合，并使用诸如均值分析 (ANOM) 和方差分析 (ANOVA) 等工具分析了响应值。除了知道所有单个参数的重要性，据观察，与激光强度和载物台速度相比，焦点水平对特征尺寸的影响很大。还讨论了这些装置在基于液滴的微流体和用于电化学传感的叉指电极领域的应用。