Laser direct writing of graphene photodetector with a wide spectral detection from the visible to the infrared

Improvements in properties of polybenzoxazine-based laser-induced graphene (LIG) by alloying with polyimide and modeling of production process

“…This improvement also implies that the 50%poly(Phdde) : 50%polyimide-LIG has a more porous structure, as it has been established that graphene structures with larger L a possess more porous structures. 29 Moreover, a signicantly lower electrical resistivity was recorded with the 50%poly(Ph-dde) : 50% polyimide-LIG (Table 3), compared to that of the 100%poly(Phdde)-LIG, with a reduction in electrical resistivity of about 37% being achieved. This nding further corroborates the improvement in porosity, as it has been established that higher porosity in LIG structures leads to lower electrical resistivity, as electrical resistivity arises from hopping of carriers between crystals.…”

“…This nding further corroborates the improvement in porosity, as it has been established that higher porosity in LIG structures leads to lower electrical resistivity, as electrical resistivity arises from hopping of carriers between crystals. 29 Observation of the surface morphology of the LIG samples (100 mm scale images in Fig. 6) reveals a ridge-like route indicating laser engraving passages, with the 50%poly(Ph-dde) : 50%polyimide-LIG exhibiting a much more pronounced ridgelike route, which could be attributed to the higher stability and char yield of the substrate.…”

“…The D peak is linked to disorders and defects in the graphene structure, while G and 2D peaks are due to carbon atom vibration because of the sp 2 hybridization in the hexagonal lattice and stacking and phonon of the graphene structure, respectively. [26][27][28][29] It could be observed that the D peak intensity in the 100%poly(Ph-dde)-LIG spectrum (Fig. 5(a)) is much more pronounced relative to the D peak intensity in the 50%poly(Ph-dde) : 50%polyimide-LIG spectrum (Fig.…”

“…This finding further corroborates the improvement in porosity, as it has been established that higher porosity in LIG structures leads to lower electrical resistivity, as electrical resistivity arises from hopping of carriers between crystals. 29 …”

“…4(b)).Fig.5(a) and (b) show Raman spectra of the LIG samples the three characteristics peaks, D, G, and 2D at 1350 cm −1 , 1580 cm −1 , and 2680 cm −1 , respectively are shown on the Raman spectra, which conrms the production of graphene on both the substrates. The D peak is linked to disorders and defects in the graphene structure, while G and 2D peaks are due to carbon atom vibration because of the sp 2 hybridization in the hexagonal lattice and stacking and phonon of the graphene structure, respectively [26][27][28][29]. It could be observed that the D peak…”