Burrow Guy M, Leibovici Matthieu C R, Gaylord Thomas K
School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0250, USA.
Appl Opt. 2012 Jun 20;51(18):4028-41. doi: 10.1364/AO.51.004028.
Multibeam interference represents an approach for producing one-, two-, and three-dimensional periodic optical-intensity distributions with submicrometer features and periodicities. Accordingly, interference lithography (IL) has been used in a wide variety of applications, typically requiring additional lithographic steps to modify the periodic interference pattern and create integrated functional elements. In the present work, pattern-integrated interference lithography (PIIL) is introduced. PIIL is the integration of superposed pattern imaging with IL. Then a pattern-integrated interference exposure system (PIIES) is presented that implements PIIL by incorporating a projection imaging capability in a novel three-beam interference configuration. The purpose of this system is to fabricate, in a single-exposure step, a two-dimensional periodic photonic-crystal lattice with nonperiodic functional elements integrated into the periodic pattern. The design of the basic system is presented along with a model that simulates the resulting optical-intensity distribution at the system sample plane where the three beams simultaneously interfere and integrate a superposed image of the projected mask pattern. Appropriate performance metrics are defined in order to quantify the characteristics of the resulting photonic-crystal structure. These intensity and lattice-vector metrics differ markedly from the metrics used to evaluate traditional photolithographic imaging systems. Simulation and experimental results are presented that demonstrate the fabrication of example photonic-crystal structures in a single-exposure step. Example well-defined photonic-crystal structures exhibiting favorable intensity and lattice-vector metrics demonstrate the potential of PIIL for fabricating dense integrated optical circuits.
多光束干涉是一种用于产生具有亚微米特征和周期的一维、二维和三维周期性光强分布的方法。因此，干涉光刻（IL）已被广泛应用于各种领域，通常需要额外的光刻步骤来修改周期性干涉图案并创建集成功能元件。在本工作中，引入了图案集成干涉光刻（PIIL）。PIIL是叠加图案成像与IL的集成。然后介绍了一种图案集成干涉曝光系统（PIIES），该系统通过在一种新颖的三光束干涉配置中纳入投影成像能力来实现PIIL。该系统的目的是在单次曝光步骤中制造二维周期性光子晶格，并将非周期性功能元件集成到周期性图案中。介绍了基本系统的设计以及一个模型，该模型模拟了在系统样品平面处的光强分布，在该平面上三束光同时干涉并集成投影掩模图案的叠加图像。定义了适当的性能指标以量化所得光子晶体结构的特性。这些强度和晶格矢量指标与用于评估传统光刻成像系统的指标有显著差异。给出了模拟和实验结果，证明了在单次曝光步骤中制造示例光子晶体结构的可行性。展示出良好强度和晶格矢量指标的示例定义明确的光子晶体结构证明了PIIL在制造密集集成光学电路方面的潜力。
