A process for making an ultra-conformal microprint by ultra-conformal microprint transferring includes: disposing a transfer moiety arranged in a microstructure on a transfer substrate; disposing a glassy transfer layer on the transfer moiety; forming a glassy composite; removing the glassy composite from the transfer substrate while maintaining the microstructure of the transfer moiety in the glassy transfer layer; disposing the glassy composite on a microprint substrate; ultra-conformally covering the microprint substrate with the glassy composite by heating the glassy composite so that it flows while maintaining the microstructure of the transfer moiety in the glassy transfer layer so that the microstructure is disposed on the microprint substrate; and removing the glassy transfer layer while leaving the transfer moiety disposed in the microstructure on the microprint substrate to form the ultra-conformal microprint including the transfer moiety arranged in the microstructure on the microprint substrate.
This invention is a new method of transferring (“transfer printing”) microstructures or micropatterns created on a first surface onto a second receiving surface, where the second surface may be highly uneven or curved or in some other way incompatible with the fabrication process requirements of the structures or patterns. The method relies on a transfer material poured over and set on the first surface. The transfer material is then removed together with the now embedded structures/patterns and placed in contact with the second surface. The transfer material specifically has a low-temperature glass transition temperature such that it can be easily reflowed (“melted”) around second surface, proving ultra-conformal contact. Finally, the transfer material is dissolved away in a benign solvent (often water), leaving the structures /patterns transfer printed over the second surface.
NOTE: Throughout, the use of the word “melt” is taken colloquially to mean raising the transfer material to a temperature near its glass transition temperature. I.e., “melt” as used here is not the scientific definition which applies only to crystal structures with a discrete melting temperature, but rather it is intended to refer instead to the gradual continuous softening behavior observable in amorphous glassy materials around their glass transition temperature, Tg.