RYJ-Ⅱ型热压成形设备实现压力均匀性的调平装置

针对热压成形设备中由于上下两热压面之间的不平行而引起的压力不均匀,设计了一种精密调平装置。对精密调平装置的设计原理、结构、调平方法和调平过程做了详细的讨论,最后通过实验验证精密调平装置能够准确的调节下热压面的姿态,使两个热压面的平行度达到10μm,实现热压过程中的压力均匀。     

Effects of contact-stress on hot-embossed PMMA microchannel wall profile

Hot-embossing (thermal-compression) based microchannel fabrication techniques have gained much attention recently due to their low-cost setup and ease of implementation. However, not much effects have been attempted in trying to understand or characterize the mechanics of the hot-embossing process in fabricating microchannels. Most research groups still rely on trial-and-error processes to hot-emboss microchannels for microfluidic control applications. The present paper describes the application of the contact-stress analysis to understand the mechanism of using molds with micro-features to hot-emboss PMMA substrates. Experimental results showing that the resulting microchannel wall profile can be predicted with good accuracy via a close-form solution of the analysis are also presented.     

面向聚合物微结构制作的热压成形设备的研制

简要介绍了聚合物微结构热压成形的基本原理以及工艺参数和成形过程,根据工艺要求,确定了热压成形设备所应具有的温度、压力控制等基本功能。研制了RYJ-Ⅰ型热压成形机,其上下热压头采用独立的温度控制,压力通过传感器进行反馈控制,在机械结构的设计上采取了几项措施,保证了上下热压头两个热压表面之间平行。控制系统的软件采用面向对象的程序设计方法,并采用了独立线程、高精度多媒体定时器、开放式数据库联接等技术,对温度、压力等进行高精度实时控制。介绍了RYJ-Ⅱ型热压成形机的研制情况,该型成形机温度、压力的控制范围大,适用于绝大多数聚合物材料微结构的制作。     

Simultaneous fabrication of line defects-embedded periodic lattice by topographically assisted holographic lithography

We have demonstrated simultaneous fabrication of designed defects within a periodic structure. For rapid fabrication of periodic structures incorporating nanoscale line-defects at large area, topographically assisted holographic lithography (TAHL) technique, combining the strength of hologram lithography and phase-shift interference, was proposed. Hot-embossing method generated the photoresist patterns with vertical side walls which enabled phase-shift mask effect at the edge of patterns. Embossing temperature and relief height were crucial parameters for the successful TAHL process. Periodic holes with a diameter of 600 nm at a 1 μm-pitch incorporating 250 nm wide line-defects were obtained simultaneously.     

用于微结构成型的新型热压机温度控制系统研究

针对利用热压方法制备可降解高分子材料微器件方面存在的温度控制问题,研究适用于热压成型机的温度控制系统。基于在可降解聚合物PLGA等材料的微结构制作过程中,温度对微结构成型质量影响的规律,设计热压成型样机中的温度控制系统。通过对可降解聚合物的低温热压成型实验,证实了所研究的温度控制系统能够实现热压温度的自动控制,并满足可降解高分子材料微结构成型的工艺要求。     

A parameter study on the micro hot-embossing process of glassy polymer for pattern replication

As a promising processing method for glassy polymer, hot-embossing process has attracted more attention in the micro/nano manufacturing field. However, the relationship between process condition and final quality has not been thoroughly and systematically investigated. Since the replication quality of the process is sensitive to the control parameter, it is necessary to study on the optimal process condition. For the four main factors influencing on the final replication fidelity of the hot-embossing process, we carried out a series of experiments with different sets of parameters, in which micro pattern arrays were directly replicated from a glassy carbon (GC) mold to a commercially available glassy polymer substrate (polycarbonate, PC) with self-made micro hot-embossing system. sWe adopt Taguchi method to minimize the sets of experiments and made an analysis of the result using ANOM and ANOVA. As the result shows, the most significant factor is the embossing temperature and the optimal process parameters are the embossing temperature at 170 °C, heating time at 120 s, embossing force at 70 kgf and force holding time at 90 s. The experiment with these parameters shows a good result.     

闪耀光栅制备工艺与结构保真性研究

针对气体检测中分光应用的闪耀光栅,该文在硅片上制备聚甲基丙烯酸甲脂(PMMA)薄膜,采用热压印及后续工艺制备了硅基的聚甲基丙烯酸甲脂闪耀光栅,通过实验分析研究了复制闪耀光栅的保真特性。研究表明,通过聚甲基丙烯酸甲脂制备、热压印及后续工艺可得到具有高保真性的微闪耀光栅,而这种方法所获得的闪耀光栅与传统方法加工的闪耀光栅相比,在效率、成本方面均具有较明显的优势。     

聚合物微结构热压成形设备的温度控制装置研究

针对一种新型可降解植入式药物载体的高效制备需要,进行聚合物多腔体微结构热压成形设备的温度控制装置和温度控制系统研制。设计了热压板与隔热板,并基于单片机和LabVIEW开发环境实现了对温度参数的测量和控制。     

聚合物微纳结构热压机的温度控制策略研究

设计实现性能良好的温度控制是聚合物微纳热压工艺探索及高质量热压加工的必要条件。对热压机温控系统进行了建模分析;将飞升曲线法和最小二乘法相结合,对系统进行了辨识;针对系统模型参数的不确定性,设计并实现了基于系统辨识整定控制参数的PID(比例-积分-微分)控制器。实验证明,此控制器超调量0.5℃、系统稳态误差±0.2℃,并且有良好的适应性,满足微纳热压工艺要求。     

微流控芯片热压成型机液压系统

提出了微流控芯片热压成型方法。介绍了热压成型的原理,并对微流控芯片热压成型机进行了总体设计。分析了热压成型机的液压系统及其器件选择方法,设计了热压成型机的整体液压回路,对液压系统进行了压力精度控制试验。试验结果表明,该系统控制精度在容许的范围之内。