Title :
A micromachined polyimide aperture for stable bilayer lipid membranes (BLMs)
Author :
Dogan, Numan S. ; Liu, L. ; Koch, A.R.
fDate :
11/1/1993 12:00:00 AM
Abstract :
Summary form only given. Silicon micromachining is used to fabricate reproducible miniature apertures over photosensitive polyimide (PPI) layers (septa), with highly controllable dimensions. PPI, having a high level of planarization, chemical inertness, a low dielectric constant, and good mechanical strength, is a very suitable material to be used as BLM septa. Apertures of ~5 μm thickness and ~40 μm diameter in PPI septa suspended over thick silicon rims were realized. The fabrication process includes double-side oxide growth on the wafer, spin-coating the PPI and its patterning, back surface anisotropic window etching, and a final cleaning step. Apertures with high circular symmetry were fabricated using this process. The BLM is formed by dropping a small amount of phospholipid-alkane solution over the PPI aperture. An initially few-μm-thick membrane spontaneously thins down to an ~50 Å thick BLM. Specific capacitance measurements of these BLMs revealed stability of up to 50 h
Keywords :
biomembranes; biosensors; capacitance measurement; etching; lipid bilayers; permittivity; polymer films; surface treatment; BLM septa; back surface anisotropic window etching; biosensor; capacitance measurements; chemical inertness; circular symmetry; cleaning step; dielectric constant; double-side oxide growth; micromachined polyimide aperture; photosensitive polyimide; planarization; reproducible miniature apertures; spin-coating; stability; stable bilayer lipid membranes; Anisotropic magnetoresistance; Apertures; Dielectric constant; Dielectric materials; Fabrication; Lipidomics; Micromachining; Planarization; Polyimides; Silicon;
Journal_Title :
Electron Devices, IEEE Transactions on
