基于界面可逆粘附的柔性可延展电子器件大规模转移印刷方法研究

Flexible and stretchable electronics composed of the semiconductor silicon, which is stretchable and retains the electrical and physical properties of the silicon, has become the hotspot of the electronics industry.?The brittle semiconductor silicon film is assembled to the soft substrate by transfer printing, through the pre-strain is applied on the soft substrate, the silicon thin film becomes wavy, which makes the structure has the electrical properties of the silicon and high stretchability. This research project, which is around the transfer printing for flexible and stretchable electronics composed of the brittle semiconductor silicon, studies the transfer printing which applied load to control the interfacial debonding, and the viscoelastic theory of the interface between soft substrate and the semiconductor silicon. In order to achieve the pick-up and printing devices in the transfer printing process, the theoretical model is established to study the loading rate control the delamination of multi-layer interfaces. In order to reduce the dependence of the transfer printing on the interfacial adhesion, the reversible adhesion transfer printing is developed to achieve reversible control of interfacial adhesion for up to three orders of magnitude change. Combination of reversible adhesion methods and large-scale local controllable transfer printing achieves economical, efficient printing method.

以半导体硅为电子元件的柔性可延展电子器件在保有半导体硅的电学和物理特性的同时依然具有高延展性，已成为电子产业的研究热点。将脆性半导体硅薄膜转移印刷到软基体上,通过对软基体施加预应变，导致硅薄膜发生屈曲变为连续性波纹形状，从而实现在不改变脆性半导体硅电学性能的情况下使得结构具有很大的延展性。本课题围绕以半导体硅为电子元件的柔性可延展电子器件的转移印刷技术，研究通过外加载荷控制界面脱粘的转移印刷技术；研究软基体与半导体硅异质界面的粘弹性理论；为了实现转移印刷过程中拾取和印刷元件两个步骤，建立了由加载速率来实现的多层界面分层脱粘的理论模型；为了减小转移印刷对界面粘附力的依赖，发展了可逆粘附转移印刷技术，实现界面粘附力达三个量级变化的可逆控制；结合可逆粘附方法和大规模局部可控的转移印刷技术实现了低成本高效率转移印刷方法。

可延展柔性无机电子器件在健康医疗和脑机融合等领域有着广泛的应用前景。转移印刷的制备方法是可延展柔性无机电子器件区别于传统半导体电子器件的主要制备技术，是柔性无机电子器件能够实现产业化的关键技术。本项目围绕柔性电子器件在大规模转移印刷过程中的界面问题，针对周期性分布的半导体元件在转印过程中对转印基体与元件以及生长基体之间的界面脱粘问题开展了研究，采用Westergaard函数方法分析了元件的周期性分布对转印基体与生长基体的沉陷接触以及在转印过程中界面的脱粘的影响。通过解析模型给出了元件尺寸和分布结构对界面脱粘的影响，发现当元件的间距大于其面内尺寸时，周期性分布对界面脱粘的影响就很小。而对间距较小时，元件的分布结构对界面的脱粘有很大的影响。这为高集成度的柔性电子器件的转印制备提供了理论支持。