High-aspect ratio submicrometer needles for intracellular applications

A processing technology is presented to produce high-aspect ratio submicrometer silicon needles suited for intracellular interfacing with living cells. Pillars are created using deep reactive ion etching, and the sharpening of the pillars is achieved by reactive ion etching. A simple polyimide-based micro-fabrication approach was developed to integrate the silicon needles with a larger silicon base designed to carry elements such as amplifier, battery or memory. The current design allows convenient handling of the device during implantation and minimal mechanical load on the implanted region. Prototype devices were tested for usability and animal compatibility.