Contact lenses that can monitor the wearer’s health and correct eyesight use embedded electronics. These, and other curved devices such as solar cells and electronics, could be manufactured using a new method called conformal additive stamp (CAS) printing.

Conformal additive stamp printing (CAS printing) was developed to manufacture curvy, three-dimensional electronics.

Electronic devices are typically manufactured in planar layouts but many emerging applications require three-dimensional curvy structures. Fabrication of such structures has proved challenging due to the lack of an effective manufacturing technology. Existing manufacturing technologies, including micro-fabrication, don’t work for curved, three-dimensional electronics because they are inherently designed to produce two-dimensional, flat electronic devices. These devices are small — ranging in size from millimeters to centimeters — with accuracy within a few microns.

With CAS printing, an elastomeric (stretchy) balloon is inflated and coated with a sticky substance. It is then used as a stamping medium, pushing down on prefabricated electronic devices to pick up the electronics and then print them onto various curvy surfaces. The method was used to create a variety of curvy devices including silicon pellets, photodetector arrays, small antennas, hemispherical solar cells, and smart contact lenses.

The work was performed using a manual version of the CAS printer, although the researchers also designed an automated version.

For more information, contact Jeannie Kever at This email address is being protected from spambots. You need JavaScript enabled to view it.; 713-743-0778.