1 Introduction to Laser Micro-to-Nano Manufacturing
43
materials synthesis and surface engineering but more research is needed in these
directions.
Femtosecond laser-induced water spliting and coal gasification have been reported
for facile synthesis of porous graphene and graphene quantum dots [150, 151]. The
underlying dynamics is not yet established but taking a critical role for large scale
synthesis of quantum dots. Femtosecond laser direct writing is also employed for
device fabrication though the laser-induced reduction of graphene oxide. The reduction should be correlated to both the photonic thermal effect and multiphotonic
absorption [98]. Recently we studied laser trimming of alloy stripes with femtosecond
laser and nanosecond pulsed laser. The precision cutting for precisive resistance
adjustment is realized by femtosecond laser trimming [152].
Multiphoton absorption of ultrafast laser is extensively used for drilling high
aspect ratio microchannel or holes in transparent materials which the linear absorption is limited [1]. Recently we reported the microball lens by forming the microcavity in polymer [21]. Shown in Fig. 1.30, a wide angle imaging is demonstrated with
Fig. 1.30 Super-wide imaging by cavity microball lens. a Super-wide imaging taken by an inverted
microscope. b Schematic for the super-angle-imaging of embedded microball lens [21, 153]
43
materials synthesis and surface engineering but more research is needed in these
directions.
Femtosecond laser-induced water spliting and coal gasification have been reported
for facile synthesis of porous graphene and graphene quantum dots [150, 151]. The
underlying dynamics is not yet established but taking a critical role for large scale
synthesis of quantum dots. Femtosecond laser direct writing is also employed for
device fabrication though the laser-induced reduction of graphene oxide. The reduction should be correlated to both the photonic thermal effect and multiphotonic
absorption [98]. Recently we studied laser trimming of alloy stripes with femtosecond
laser and nanosecond pulsed laser. The precision cutting for precisive resistance
adjustment is realized by femtosecond laser trimming [152].
Multiphoton absorption of ultrafast laser is extensively used for drilling high
aspect ratio microchannel or holes in transparent materials which the linear absorption is limited [1]. Recently we reported the microball lens by forming the microcavity in polymer [21]. Shown in Fig. 1.30, a wide angle imaging is demonstrated with
Fig. 1.30 Super-wide imaging by cavity microball lens. a Super-wide imaging taken by an inverted
microscope. b Schematic for the super-angle-imaging of embedded microball lens [21, 153]