110 likes | 222 Views
NanoFab Trainer. Nick Reeder nick.reeder@sinclair.edu June 28, 2012. NanoFab Trainer. Educational tool that lets user see the results of performing sequences of basic nano -fabrication operations on a silicon (Si) wafer. Runs under Windows operating system.
E N D
NanoFabTrainer Nick Reeder nick.reeder@sinclair.edu June 28, 2012
NanoFabTrainer • Educational tool that lets user see the results of performing sequences of basic nano-fabrication operations on a silicon (Si) wafer. • Runs under Windows operating system. • Written in LabVIEW 2009; requires LabVIEW 2009 Run-Time Engine (free download athttp://joule.ni.com/nidu/cds/view/p/id/1600/lang/en).
User Operations • Ion implantation (“doping”) • Thermal oxidation • Photolithography • Depositing layers of material • Removing material
Ion Implantation • Modifies the electrical characteristics of the silicon wafer. Such modification is the key technique underlying the operation of semiconductor devices (diodes, transistors, thyristors). • Implanting boron results in “p-type” doping. • Implanting phosphorus results in “n-type” doping.
Example: Fabricating a MOSFET • MOSFET = Metal-oxide-semiconductor field effect transistor
Thermal oxidation • Grows a layer of silicon dioxide (SiO2) on the wafer surface. • Key properties of SiO2: • Impervious to ion implantation. • Can be etched away by immersion in hydrofluoric acid (HF), which does not etch silicon.
Photolithography • Steps in photolithography: • Spin-coat photoresist. • Create and place mask. Mask defines which areas will be exposed to UV light and which areas will be shaded. • Expose with UV light. • “Develop” the photoresist: UV-exposed areas are removed, while shaded areas remain. • Wikipedia http://en.wikipedia.org/wiki/Photolithography
Depositing Layers • Methods of depositing layers of material • Electron-beam evaporation • Chemical vapor deposition (CVD) • Sputtering • The materials deposited may be metals, dielectrics, or semiconductors.
Removing material • Methods of removing material • Wet etching • Low-tech • Immerse wafer in a bath of liquid acid or solvent • Dry etching • High-tech • Expose wafer to plasma beam
Other Features of Trainer • Maintains history of user operations. • Will track cost, time, and quality of user operations. • “Tutorial” page will provide photos and videos of operations being performed in the lab, along with text explaining theory.