Fabrication of the Silicon-Based Three-Dimension Neural Probe Arrays

Abstract

The neural probe array is an important tool for getting the neural signals. Giving consideration to the biological compatibility and the demand of integrating in circuit, new fabrication process of a silicon-based three-dimension neural probe array was reported. The idea about milling in mechanical process and the method of structure for transfer were introduced in the fabrication. The 10*10 scale silicon-based three-dimension probe arrays integrated in the readout circuit directly were fabricated by means of flip chip and multi-blade mixing dicing techniques. In the entire fabrication process, no any high-temperature process and silicon wet etching process, which would damage the circuit, were included. Using the fabrication process above, the 10*10 scale silicon-based probe arrays with centre-to-centre separation of 400 μm were achieved. In the probe arrays, whose good rate was more than 95%, the width of a single probe was 100 μm, the tip angle was 25o, and the height was more than 1.4 mm. Through the fabrication process, it was not only reducing the pin count greatly, but also simplifying the interface effectively. By the in vivo experiment of the Sprague Dawley rat, the corresponding nerve signal was obtained.