Department of Chemistry, Memorial University, St. John's, NL, Canada.
Sensors (Basel). 2013 May 28;13(6):7021-32. doi: 10.3390/s130607021.
We present and analyze a method to improve the morphology and mechanical properties of gold thin films for use in optical sensors or other settings where good adhesion of gold to a substrate is of importance and where controlled topography/roughness is key. To improve the adhesion of thermally evaporated gold thin films, we introduce a gold deposition step on SU-8 photoresist prior to UV exposure but after the pre-bake step of SU-8 processing. Shrinkage and distribution of residual stresses, which occur during cross-linking of the SU-8 polymer layer in the post-exposure baking step, are responsible for the higher adhesion of the top gold film to the post-deposition cured SU-8 sublayer. The SU-8 underlayer can also be used to tune the resulting gold film morphology. Our promoter-free protocol is easily integrated with existing sensor microfabrication processes.
我们提出并分析了一种改进金薄膜形貌和力学性能的方法，该方法可用于光学传感器或其他需要金与基底良好附着且控制形貌/粗糙度的应用场合。为了提高热蒸发金薄膜的附着力，我们在 SU-8 光刻胶上进行金沉积，然后再进行 UV 曝光，但要在 SU-8 处理的预烘烤步骤之后。在曝光后烘烤步骤中 SU-8 聚合物层交联过程中发生的收缩和残余应力分布是导致顶部金膜与后沉积固化 SU-8 亚层更高附着力的原因。SU-8 底层也可用于调整所得金膜的形貌。我们的无促进剂方案很容易与现有的传感器微制造工艺集成。
