Department of Bioengineering, University of Illinois at Chicago, 851 S. Morgan Street, Chicago, Illinois 60607, United States.
Department of Biomedical Engineering, The State University of New York at Binghamton University, P.O. Box 6000, Binghamton, New York 13902, United States.
ACS Appl Mater Interfaces. 2020 Sep 30;12(39):44371-44380. doi: 10.1021/acsami.0c13712. Epub 2020 Sep 17.
In modern biomaterial-based electronics, conductive and flexible biomaterials are gaining increasing attention for their wide range of applications in biomedical and wearable electronics industries. The ecofriendly, biodegradable, and self-resorbable nature of these materials makes them an excellent choice in fabricating green and transient electronics. Surface functionalization of these biomaterials is required to cater to the need of designing electronics based on these substrate materials. In this work, a low-temperature atomic layer deposition (ALD) process of platinum (Pt) is presented to deposit a conductive thin film on collagen biomaterials, for the first time. Surface characterization revealed that a very thin ALD-deposited seed layer of TiO on the collagen surface prior to Pt deposition is an alternative for achieving a better nucleation and 100% surface coverage of ultrathin Pt on collagen surfaces. The presence of a pure metallic Pt thin film was confirmed from surface chemical characterization. Electrical characterization proved the existence of a continuous and conductive Pt thin film (∼27.8 ± 1.4 nm) on collagen with a resistivity of 295 ± 30 μΩ cm, which occurred because of the virtue of TiO. Analysis of its electronic structures showed that the presence of metastable state due to the presence of TiO enables electrons to easily flow from valence into conductive bands. As a result, this turned collagen into a flexible conductive biomaterial.
在现代基于生物材料的电子学中，导电和柔性生物材料因其在生物医学和可穿戴电子行业的广泛应用而受到越来越多的关注。这些材料具有环保、可生物降解和可自我吸收的特性，因此在制造绿色和瞬态电子产品方面是绝佳的选择。为了满足基于这些基底材料设计电子器件的需求，需要对这些生物材料进行表面功能化处理。在这项工作中，首次提出了在胶原生物材料上低温原子层沉积（ALD）铂（Pt）的方法。表面特性分析表明，在 Pt 沉积之前，在胶原表面沉积一层很薄的 TiO 原子层沉积种子层，是在胶原表面实现超薄 Pt 更好成核和 100%表面覆盖率的一种替代方法。从表面化学特性分析中证实了存在纯金属 Pt 薄膜。电学特性分析证明，在胶原上存在连续且导电的 Pt 薄膜（∼27.8 ± 1.4nm），其电阻率为 295 ± 30 μΩ·cm，这是由于 TiO 的存在所致。对其电子结构的分析表明，由于 TiO 的存在，存在亚稳态使得电子很容易从价带流向导带。结果，这使得胶原变成了一种柔性导电生物材料。
