SBIR Phase II: Nanometer-Level Fidelity in Maskless Lithography

这个小型企业创新研究(SBIR)第二阶段项目旨在开发一种无掩膜光刻系统，以确保其写入的图案在1纳米以下的水平上没有位置误差(即失真)。在传统的光刻中，失真最小化取决于图像投影透镜的设计和构造以及掩模的保真度。测量1纳米和1纳米以下的几何缺陷在智力上是具有挑战性的。在第一阶段项目中，开发了一种共焦计量系统(CMS)，以根据主参考光栅扫描通过焦点时产生的周期信号的相位来确定焦点位置。在这一第二阶段项目中，将在图案编写软件中进行更正。工作台X-Y位置的误差将通过比较主参考光栅的读数和安装在工作台中的编码器的读数来确定。一旦知道，系统错误将在软件中通过一种称为重复压裂的过程进行纠正。CMS将使位于不同地点的系统能够引用共同的基准，从而实现相同的图案保真度。该项目的更广泛/商业影响将是为定制电子产品和光电子产品的小批量制造以及未来的纳米制造提供高保真的无掩膜光刻工具的潜力。与现有的电子束系统相比，这种无掩膜光刻工具将提供更高的吞吐量、非真空处理、大面积连续图案化、更低的成本和不会失真到1 nm以下的水平。

This Small Business Innovation Research (SBIR) Phase II project aims to develop a maskless photolithography system by ensuring that the patterns it writes are free of positional error (i.e., distortion) to the sub-1 nm level. In traditional photolithography, distortion minimization depends on the design and construction of an image-projection lens and on the fidelity of the mask. Measuring 1nm and sub-1nm geometric imperfections is intellectually challenging. In Phase I project, a confocal-metrology-system (CMS) was developed to determine focal spot positions from the phase of periodic signals produced when a master reference grating is scanned through the focal spots. In this Phase II project, corrections will be applied in the pattern-writing software. Errors in the X-Y position of the stage will be determined by comparing readings from a master reference grating with readings from the encoder built into the stage. Once known, systematic errors will be corrected in software through a process known as refracturing. The CMS will enable the systems located at disparate sites to reference a common fiducial, thus achieving identical patterning fidelity. The broader/commercial impacts of this project will be the potential to provide a maskless photolithography tool with high fidelity for low-volume manufacturing of custom electronics and photonics, and for future nanomanufacturing. In comparison to existing electron-beam systems, this maskless photolithography tool will provide higher throughput, non-vacuum processing, large-area continuous patterning, lower cost and freedom from distortion to the sub-1nm level.