  The demand for higher resolution displays drives the demand for smaller
pixels. Displays show a trend of doubling the pixel number every 4 years and
doubling the pixel per inch (PPI) every 6 years. As the prospective candidate
for next-generation display technology, microLED (micro Light Emitting Diode)
will suffer from sidewall current leakage and poor extraction efficiency as its
lateral size reduces. Using Finite Element Analysis (FEA) method and
Finite-Difference Time-Domain (FDTD) method, we find that reducing the
thickness of the LED can reduce the current leaking to the sidewalls and reduce
the total internal reflection simultaneously. A promising solution to this
problem is by using atomically thin 2D materials to make LEDs. However,
monolayer inorganic 2D materials that can provide red, green and blue emission
are still lacking. Based on the blue light-emitting material fluorographene
(CF), partially fluorinated graphene (CFx) is synthesized in this work to emit
red and green colors from 683 nm to 555 nm (limited by the instrument). This
work also demonstrates lithographically defined regions with different colors,
paving the way for the scaling of microLED.
