SBIR Phase II: Nanometer-Level Fidelity in Maskless Lithography

这个小型企业创新研究（SBIR）二期项目旨在开发一种无掩膜光刻系统，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）。在传统的光刻技术中，最大限度地减少失真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1nm和亚1nm的几何缺陷在智力上具有挑战性。在第一期项目中，开发了共焦计量系统（CMS），通过主参考光栅扫描焦点光斑时产生的周期信号相位来确定焦点光斑的位置。在这个第二阶段的项目中，将在模式书写软件中应用校正。台上X-Y位置的误差将通过比较主参考光栅的读数和台上内置编码器的读数来确定。一旦已知，系统错误将通过重复压裂过程在软件中进行纠正。CMS将使位于不同地点的系统能够引用一个共同的基准，从而实现相同的模式保真度。该项目的更广泛/商业影响将是为定制电子和光子学的小批量制造以及未来的纳米制造提供高保真度的无掩膜光刻工具。与现有的电子束系统相比，这种无掩模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，更低的成本以及在亚1nm级别上不失真。

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.