A high integration 3D temperature controllable micro-reactor fabricated by femtosecond laser wet etching

Microfluidic chips and microreactors have been widely used in various fields due to their low reagent consumption, fast reaction speed and good safety. Besides, temperature is the key parameter of many biochemical reactions. So it is important for the creation of temperature controllable micro-reactor. However, There are some problems in existing micro-reactors, such as structure, size, temperature control method and temperature distribution. Here we report a method based on an improved femtosecond laser wet etching technology and metal-microsolidifying process for the fabrication of microchannel and 3D microcoils inside fused silica. Based on this approach, we fabricate a temperature controllable micro-reactor used for polymerase chain reaction (PCR) by integrating 3D metallic microcoils and microfluidic channel twined by microcoils inside fused silica. We precisely and conveniently get required temperature by varying the voltage of microcoils. The micro-reactor also exhibits a high integration level and good uniformity of temperature distribution. In addition, we get a miniaturized device which can be conveniently integrated.