Nonthermal Effect of Microwave Processing Enhances Interface Reactivity and Microchannel Integrity: Low-Temperature Rapid Bonding of PMMA Microfluidic Devices.

As a nonthermal approach, microwave processing significantly enhances interface reactivity and preserves microchannel integrity during the bonding of poly(methyl methacrylate) (PMMA) microfluidic devices. By activating and aligning polymer chains at lower temperatures, this method promotes rapid bonding and improved interfacial adhesion, maintaining the precision of delicate microstructures essential for device functionality. Unlike thermal wafer bonding, which relies on elevated temperatures that may risk deforming delicate microstructures, the nonthermal effect of microwaves facilitates the activation and alignment of polymer chains at lower temperatures, enhancing interfacial adhesion through improved molecular interactions.

Forming a Photoluminescent Layer on Another Surface in the Dark through Lasering of N-Type Silicon in an Electrolyte.

Photoetching of n-type silicon induces a photoluminescent (PL) layer containing nanocrystals on the irradiated surface, usually through band gap absorption (wavelength <1100 nm). Here, we demonstrate the formation of a PL layer restricted to the backside surface, not the irradiated surface, by using a 1064 nm Nd:YAG laser. A nanoscale structure of the PL layer is achieved by merely modifying the electrolyte concentration without adding oxidants.