Formation of highly conductive and optically transparent multilayer graphene films by carbonization of polyimide Langmuir–Blodgett films

For the first time, multilayer graphene films on quartz glass were obtained by carbonization of the Langmuir–Blodgett films of polyimide. On the Raman spectra of the carbonized polyimide films, the $G$, $D$ bands and a wide band in the region of 2300–3200 cm$^{-1}$ were observed. Using the method of transmission microscopy, it was shown that films consist of “stacks” of layers with a interlayers distance of 0.36 nm. The surface resistance of films 5 nm thick was 1.2 $\pm$ 0.2 k$\Omega$, and the transmittance was 87% at $\lambda$ = 550 nm. In the infrared region of the spectrum, the transmittance was 97%, and in the UV region 70–80%.