NU 2005-039

Inventors

Min Hyung Lee

Joel Adam Henzie

Teri Odom*

Eun Kwak

Short Description

A novel high throughput method for fabricating free-standing hole array films with precise dimensions and spacing

Abstract

Northwestern researchers have developed a novel high throughput method for fabricating free-standing hole array films with precise dimensions and spacing.  Hole arrays are generally produced by focused ion beam (FIB) milling, a serial, low throughput process. While free-standing suspended films may be fabricated by FIB and reactive ion etching, the generation of multi-layered films has been limited to a few metals.  This new invention employs a combination of phase-shifting photolithography, wet-chemical etching, and electron-beam deposition to generate single or multiple material films of desired thickness.  Enhanced transmission and standing wave patterns are generated by coupling light to the subwavelength hole arrays using surface plasmon resonances.  The process enables construction of anisotropic hole arrays of varying size, shape, configuration, curvature and pitch.  This technology produces optical quality hole arrays in a parallel fashion from multiple materials and in areas larger than hundreds of square microns.  The tailorable combination of hole materials, shapes and polarized radiation afford a wide range of spectroscopic outputs with potential nanophotonic and sensing applications. This technology provides a flexible strategy to create subwavelength films whose properties are tunable for applications in microcopy, sensors, magneto-optic data storage, and solar cells.

Applications

• Microscopy
• Sensors
• Magneto-optic data storage
• Solar cells

Advantages

• Simple
• High Throughput
• Ability to generate large area films
• Ability to multi-layer with exceptional dimensional and thickness control

IP Status

US Issued Patent No. 7,999,353