宋晓圆 刘军山

摘要：为了在聚酰亚胺（polyimide ，PI ）基底上实现纳米裂纹的图案化，提出了一种利用不同金属薄膜在柔性基底上的延展性差异引导纳米裂纹可控分布的方法，制作出了一种具有快速响应能力的纳米裂纹应变传感器。在 PI 基底上先溅射了一层铬薄膜，对铬薄膜图形化后再溅射了一层金薄膜，制作了一种 PI基底-图形化铬中间层-金薄膜的结构。使用电子动静态万能材料试验机拉伸 PI基底，并使用扫描电子显微镜观察表层金薄膜纳米裂纹的产生情况，因为 PI 基底上的铬薄膜与金薄膜存在明显的延展性差异，金薄膜上的纳米裂纹仅在铬薄膜的存在区域内产生，产生方向与拉伸方向垂直，成功实现了金薄膜上纳米裂纹的可控分布。基于提出的纳米裂纹图案化方法，进一步在 PI 基底上制作了一种纳米裂纹应变传感器，并对制作的纳米裂纹应变传感器进行了测试。测试结果表明，制作的纳米裂纹应变传感器的响应时间短于16 ms ，具备快速响应的能力。

关键词：应变传感器;纳米裂纹;快速响应;聚酰亚胺

中图分类号：TP212                文獻标志码：A

文章编号：1009-9492（2021）12-0007-03

开放科学（资源服务）标识码（OSID）：

A Fast-response Nanocrack-based Strain Sensor

Song Xiaoyuan ，Liu Junshan ※

（ Key Laboratory for Micro/Nano Technology and System of Liaoning Province， Dalian University of Technology， Dalian， Liaoning 116024， China）

Abstract： In order to realize the patterning of nanocracks on polyimide （PI） substrates， a method to induce the controllable distribution of nanocracks  via  the  difference  in  stretchability  of  different  metal  films  on  a  flexible  substrate  was  proposed，  and  a  fast-response nanocrack-based strain sensor was fabricated. A chromium film was sputtered on a PI substrate， and a gold film was sputtered after patterning the chromium film. A PI substrate-patterned chromium intermediate layer-gold film structure was obtained. The PI substrate was stretched using the electronic dynamic and static universal material testing machine and the occurrence of nanocracks in the gold film was observed using the scanning electron microscope. Due to the obvious difference in stretchability between the chromium film and the gold film on the PI substrate， the nanocracks in the gold film were only occurred in the area supported by the chromium intermediate layer， the direction of the pattern was perpendicular to the stretching direction， and the controllable distribution of nanocracks in the gold film was realized. Based on the proposed nanocracks patterning method， a nanocrack-based strain sensor on the PI substrate was further fabricated and tested. The results showed that the response time of the nanocrack-based strain sensor was shorter than 16 ms， achieving a fast response.

Key words： strain sensor; nanocrack; fast-response; polyimide

0 引言

应变传感器是一种通过测量物体的相对变形量来获取对应物理量信息（应变[1-3]、压力[1， 3]、温度[4]、振动[1]等）的传感器，被广泛应用于生理信号采集[1， 3]、人机交互[5]等领域。其中，纳米裂纹应变传感器相对于传统金属应变片具有更高的灵敏度[6-7]。在柔性基底上实现金属纳米裂纹的精准、可控分布，能够极大地提升相应的柔性电子器件的性能，具有重要的科学意义和实际应用价值。……