The Nano Channels’s Beautiful colors are actually very useful..!

The thickness of the liquid sample is crucial for obtaining a good resolution TEM image, and so is having the right thickness of the Nano Channels. This thickness can be verified just by looking at them in the optical microscope and with the help of a ‘Color interference chart’.

When the Nano Channels are filled with air, the light reflects off of the two membrane surfaces each separated by the thickness of the nano channel. This creates interference which changes the color of the light returning to the microscope lens. The color corresponds exactly to the thickness of the channel, for a given thickness of nitride. 🔬 For instance, the circled area on the chart highlights a nitride thickness of 50 nm, aligning with the zero thickness channels at the bottom and a channel height of roughly 330 nm in the chip (see attached images).

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