Abstract
Polydimethylglutarimide (PMGI)-based resists are finding increasing use in microelectromechanical systems (MEMS) as both sacrificial and structural materials. PMGI-based resists are commercially available and were originally designed for use in bilayer lift-off applications. Literature on deep-UV exposure and development of PMGI films is limited to films less than 2.5 μm in thickness, and use only tetramethylammonium hydroxide (TMAH)-based developers. We investigate the exposure and development of PMGI films greater than 6 μm in thickness using the two main classes of developer for PMGI, TMAH, and tetraethylammonium hydroxide (TEAH)-based developers. At these thicknesses, a nonuniform dose through the film due to the optical absorption of the PMGI leads to large gradients in the dissolution properties. We report etch rates as a function of surface dose and development time. Additionally a model is developed to provide a basic predictor of development depth and other important data for fabrication process planning and development.
| Original language | English (US) |
|---|---|
| Article number | 023003 |
| Journal | Journal of Micro/Nanolithography, MEMS, and MOEMS |
| Volume | 7 |
| Issue number | 2 |
| DOIs | |
| State | Published - 2008 |
| Externally published | Yes |
Keywords
- Absorption
- Deep ultraviolet
- Lithography
- Microelectromechanical systems
- Polymers
- Thin films
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
- Mechanical Engineering
- Electrical and Electronic Engineering