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M. Zhong and P. Fan
applications of the proposed new methods as well as the prepared metal surface micronano structures in the fields like photothermal conversion, photoelectrocatalysis, and
optoelectronic devices are explored.
In the present chapter, a brief overview of the state-of-the-art and current challenges of antireflection SMNS, especially those fabricated by laser, is provided first.
After that, the specific methods we developed with high repetition rate high power
ultrafast lasers for fabricating SMNS on metals are introduced in Sect. 2.3. The
antireflection performances of the fabricated SMNS are demonstrated in detail in
the following part, which is further organized into three sections according to the
scale features of SMNS: (Sect. 2.4) antireflection of nanoscale structures, (Sect. 2.5)
antireflection of micro-nano dual-scale structures, and (Sect. 2.6) antireflection of
multiscale structures. In the last Sect. 2.7, some representative applications of the
SMNS we constructed are presented. This chapter intends to offer readers both an
integrated tour of laser fabrication technologies for SMNS and a basic realization of
their great application prospects.
2.2 Overview of Research
2.2.1 Micro-nano Structures on Semiconductor Surfaces
for Antireflection
Silicon is the most widely used semiconductor material. The antireflection structures
on Si surfaces are essential for enhancing their light absorption and improving their
performances particularly in photovoltaic and photodetector fields. In 1999, Eric
Mazur et al. [22] in Harvard University produced conical spike arrays on silicon
surfaces through fs laser irradiation and reduce its surface reflectance down to below
10% in the spectrum of UV (0.25 µm) to the near-infrared (2.5 µm), which is called
“Black Silicon”. After that, a number of similar shaped Si surface structures with
varied geometrical dimensions have been fabricated, not only by lasers but also by
other methods, in order to continuously improve their antireflection properties [23,
24]. In 2007, for example, Huang et al. [25] prepared arrayed Si nanotips with a
base diameter of ~200 nm and lengths up to 16,000 nm through plasma etching,
achieving highly efficient antireflection performances over through the ultrabroad
spectrum range from 0.25 to 200 µm.
Encouraged by the success of antireflection SMNS on Si, the research on
antireflection SMNS on other semiconductor materials has also been extensively
conducted, especially on the gallium-based semiconductors like GaAs [26], GaN
[27], GaP [28], etc. Song et al. [26] use a two-beam laser interference method to
fabricate closely packed and aspect-ratio-controlled subwavelength grating structures on GaAs surfaces, the measured reflectance values of which are below 5% over
a wide wavelength range of 300–1100 nm.
M. Zhong and P. Fan
applications of the proposed new methods as well as the prepared metal surface micronano structures in the fields like photothermal conversion, photoelectrocatalysis, and
optoelectronic devices are explored.
In the present chapter, a brief overview of the state-of-the-art and current challenges of antireflection SMNS, especially those fabricated by laser, is provided first.
After that, the specific methods we developed with high repetition rate high power
ultrafast lasers for fabricating SMNS on metals are introduced in Sect. 2.3. The
antireflection performances of the fabricated SMNS are demonstrated in detail in
the following part, which is further organized into three sections according to the
scale features of SMNS: (Sect. 2.4) antireflection of nanoscale structures, (Sect. 2.5)
antireflection of micro-nano dual-scale structures, and (Sect. 2.6) antireflection of
multiscale structures. In the last Sect. 2.7, some representative applications of the
SMNS we constructed are presented. This chapter intends to offer readers both an
integrated tour of laser fabrication technologies for SMNS and a basic realization of
their great application prospects.
2.2 Overview of Research
2.2.1 Micro-nano Structures on Semiconductor Surfaces
for Antireflection
Silicon is the most widely used semiconductor material. The antireflection structures
on Si surfaces are essential for enhancing their light absorption and improving their
performances particularly in photovoltaic and photodetector fields. In 1999, Eric
Mazur et al. [22] in Harvard University produced conical spike arrays on silicon
surfaces through fs laser irradiation and reduce its surface reflectance down to below
10% in the spectrum of UV (0.25 µm) to the near-infrared (2.5 µm), which is called
“Black Silicon”. After that, a number of similar shaped Si surface structures with
varied geometrical dimensions have been fabricated, not only by lasers but also by
other methods, in order to continuously improve their antireflection properties [23,
24]. In 2007, for example, Huang et al. [25] prepared arrayed Si nanotips with a
base diameter of ~200 nm and lengths up to 16,000 nm through plasma etching,
achieving highly efficient antireflection performances over through the ultrabroad
spectrum range from 0.25 to 200 µm.
Encouraged by the success of antireflection SMNS on Si, the research on
antireflection SMNS on other semiconductor materials has also been extensively
conducted, especially on the gallium-based semiconductors like GaAs [26], GaN
[27], GaP [28], etc. Song et al. [26] use a two-beam laser interference method to
fabricate closely packed and aspect-ratio-controlled subwavelength grating structures on GaAs surfaces, the measured reflectance values of which are below 5% over
a wide wavelength range of 300–1100 nm.