Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
736177 | Sensors and Actuators A: Physical | 2015 | 6 Pages |
•The sensitivity of based QD detector was improved.•The photosensitive device exhibits a very high photoresponsivity.•The signal-to-noise ratio enables high sensitivity to very low photon powers.•Depletion of the surface states can be a way to increase the sensitivity.•The results were compared with simulations modeling program.
In this paper we demonstrate a very sensitive near-infrared light detector device based on InAs nano crystals (NCs) acting as an optical gate on top of a high-mobility shallow two-dimensional electron gas channel. The ability to integrate electronics with the NCs using both top-down and bottom-up approaches allows to utilize the NCs unique quantum properties for future optoelectronic devices. We employ wet chemistry to self-assemble the organic monolayers and the NCs on top of the field effect transistor. By using shallow and very narrow channel, the device's quantum efficiency can go as high as 106 V/W at room temperature, with a signal-to-noise ratio that enables sensitivity for very low photon power. We find that our experimental results are compatible with simulation. Lastly, the route to advance to the single photon detection limit is discussed.