Large-scale and contact-free fabrication of microwell arrays based on electro-pressure of depositing ions

Microwell arrays are showing great potentials for various optoelectronic and biological applications. However, large-scale fabrication of microwell arrays remains a big challenge to modern micro- and nanotechnology. Here, we report a novel fabrication method that can produce massive aligned microwells in a cost-effective way. With using ionic wind, the hole arrays of pre-fabricated masks can be projected on polymer films and form microwell arrays in a contact-free way, and at high efficiency. Thousands of microwells can be rapidly fabricated in several minutes with their parameters, such as shape, size, and density, being widely tunable, through adjusting the mask’s design and its location in the ionic wind. The fabricated circle and square holes in microwells perfectly replicate the features from the mask, thus being successfully used to trap suspension cells and culture them sustainably till significant cell patterns are formed.