Printing of Electronic Nanoinks by Laser Forward Transfer

Abstract

Laser forward transfer processes are capable of directly generating patterns and structures of functional materials for the rapid prototyping of electronic, optical and sensor devices. These processes, also known as laser induced forward transfer or LIFT, offer unique advantages and capabilities for digital microfabrication. A key advantage of laser forward transfer techniques is their compatibility with a wide range of materials, surface chemistries and surface morphologies. These processes have been demonstrated in the fabrication of a variety of microelectronic elements such as interconnects, passives, antennas, sensors, power sources and embedded circuits. Overall, laser forward transfer is perhaps the most flexible digital microfabrication process available in terms of materials versatility, substrate compatibility and range of speed, scale and resolution. Recently, laser forward transfer of thin film-like structures with excellent lateral resolution and thickness uniformity using metallic nanoinks has been shown at NRL using a technique named laser decal transfer. The high degree of control in size and shape achievable with laser decal transfer has been applied to the digital microfabrication of 3-dimensional stacked assemblies and freestanding structures for MEMS applications. This paper will describe the unique advantages and capabilities of laser decal transfer of electronic nanoinks, discuss its applications and explore its role in the future of digital microfabrication.