Presentation Short Title Engr 1182 Nano Pre-Lab Chip Lid Molding Rev: 20XXMMDD, Initials Presentation Short Title

Presentation Short Title Micro-fabrication How can we produce devices on a very small scale ? E.g Device dimensions 10 nm – 400 µm Answer: Two ways Top – Down conventional manufacturing approaches at a reduced scale, such as CNC milling and photolithography Bottom – Up controlling molecular-level interactions to create substances with the required properties Reference: Nick Ferrell P. 2 Rev: 20XXMMDD, Initials Presentation Short Title

Evolution of Top – Down Micro-fabrication Originally developed by microelectronics silicon industry Refined for nanoscale fabrication Extended to polymer micro/nanofabrication polymers are flexible and bio-compatible Rev: 20XXMMDD, Initials Presentation Short Title

Presentation Short Title Photolithography Photolithography is a common micro-fabrication technique used to transfer an image from a photomask to the surface of a substrate by using ultraviolet light. The components needed for Photolithography are light source, photomask, lens and wafer. Rev: 20XXMMDD, Initials Presentation Short Title

Presentation Short Title LOC fabrication For this LOC project chips will be produced in a three step process. First, each team creates a CAD file of their LOC design. Second, acrylic wafers are milled with a CNC machine from the CAD design. Third, we will mold plain lids (no pattern) to enclose the channels and wells of the acrylic wafer. Rev: 20XXMMDD, Initials Presentation Short Title

Presentation Short Title Molding LOC wells and channels will be sealed with a flexible lid. In order to mold our LOC lids, we mix PDMS (silicone rubber) resin with its hardener(catalyst) in a disposable cup by stirring rigorously. This mixing creates a lot of bubbles and we need to get rid of those bubbles since we do not want any optical defects in our molds. Rev: 20XXMMDD, Initials Presentation Short Title

Presentation Short Title Degassing Liquids We get rid of those bubbles by pulling a vacuum on solution. Lower pressure expands bubbles by increasing the volume of the gas Lower pressure reduces the solubility of air in the liquid thus causing bubbles to surface. Cycling vacuum and atmospheric pressure creates a driving force to remove bubbles from the liquid phase and have a defect free mold. Rev: 20XXMMDD, Initials Presentation Short Title