The objective of this Phase II program is to complete the development of a commercializable solid state nanopore device for the accurate high speed sequencing of DNA. To achieve this goal a manufacturable device must be designed and fabrication processes established that result in a unit with extremely small, well controlled diameter orifices of approximately 2 nm through a multi-layered thin film sandwich of insulators and conductors. The Phase I portion of this program established the methodology of: creating a thin (30 nm) SiN film over a 20 um square window in a 1 cm square silicon frame; Focused Ion Beam (FIB) milling a nanopore; subsequent deposition of a multi-layer thinfilm sandwich of conductor and insulating layers on the surface of SiN film; and building a cartridge to hold and seal the nanopore chip between two liquid cells, and provide electrical terminations for measuring the changes in current, potential, or capacitance resulting in the passage of a DNA molecule chain through the nanopore. It was found that FIB milling produced a nanopore that was too wide and lacked the required sensitivity to map DNA molecules passing through the nanopore.. A new approach, TEM drilling will be used to achieve nanopores of 2 nm or smaller. Additional work will be invested in optimizing the leads and instrumentation, i.e., patch clamp amplifiers to achieve improved signal-to-noise ratios and increased detection sensitivity.
