Project Overview
Non-volatile memories (NVM) are fascinating as they demonstrate a non-linear dynamic behavior, creating a hysteresis and retains data even when power is turned off. NVMs are used in storage devices (SSD, memory cards, USB flash drives) which are integral to data storage in everything from consumer electronics to enterprise data centers. It also has a faster read and write speeds compared to other devices such as DRAM, optical drives and tap storages.
My first step towards achieving a NVM-like device is creating a MEMS device using SOI standard wafer technology that is driven by AC/DC signals and DC bias voltage for the artificial polysilicon beam that would be electrostatically actuated and achieve a pull-in voltage state. This would allow us to determine the stable states and understand the reliable ranges of the memory bit.
Key Softwares / Applications
COMSOL
- created a 3D simulation of the polysilicon beam with air filled boundary conditions / grounded substrate to electrostatically actuate the beam. Created a custom moving mesh that would bring accurate results of deforming geometries (beam)
- included relevant 1D plots (electric potential, displacement with applied voltage, and capacitance) to understand the simulation results
KLayout
- created numerous drafts of the mask layer (device layer) including different necessary masks — TRENCH, PADMETAL, SOI, and SOI Hole — while complying with important desing rules for plausible processing in the lab.
- the device layer incorporates two electrodes (DC bias to the beam and grounded substrate) which enables the electrostatic actuation. My next step is to include the AC signal for the ideal three electrode simulation.
Onshape
- Before using COMSOL geometries, I utilized Onshape to create the beam using different materials (6061 aluminum alloy, silicon, 6063 aluminum), double clamp (2 fixed constraints) with a uniform load for rudimentary simulations.
- Hand-calculated the internal beam loads (bending moment and shear force) to match with the simulation under different applied forces
