Provided is a method of synthesizing apatite powder by emitting a laser beam to a surface of a substrate immersed in a precursor solution. The method is including immersing a substrate in an apatite-forming precursor solution, emitting a laser beam to a region on a surface of the substrate immersed in the precursor solution, and obtaining apatite powder generated in the precursor solution.

Provided is a method of synthesizing apatite powder by emitting a laser beam to a surface of a substrate immersed in a precursor solution. The method is including immersing a substrate in an apatite-forming precursor solution, emitting a laser beam to a region on a surface of the substrate immersed in the precursor solution, and obtaining apatite powder generated in the precursor solution.

Provided is a method for preparing gold nanorods having a high catalytic activity by using a femtosecond laser. The method includes: (1) preparing a gold seed solution; (2) preparing a gold nanorod solution by a seed solution growth process; (3) subjecting the gold nanorod solution to a centrifugal separation to obtain the gold nanorods, and dropping the gold nanorods on a silicon substrate; (4) building a system for preparing the gold nanorods having the high catalytic activity by using the femtosecond laser; and (5) emitting a pulse of the femtosecond laser on the silicon substrate, to allow an electric field distribution of a surface of the gold nanorod on the silicon substrate to change, to partially exfoliate atoms on the surface of the gold nanorod, thereby obtaining the gold nanorod with the high catalytic activity.

Embodiments of the present invention are directed to a surface modified metal piece comprising a first major surface, wherein at least one portion of the first major surface: comprises the reaction product of a surface modifier; has a random micro- and nanoscale structure; and has at least one of a water contact angle when exposed to water of at least about 120° and a spectral reflectance of less than about 25% within the visible spectrum. Other embodiments relate to processes and methods for making such a surface modified metal piece.

A laser processing apparatus includes a liquid supply mechanism at an upper portion of a holding unit. The liquid supply mechanism includes: a liquid chamber provided with a transparent plate located with a gap formed between the transparent plate and an upper surface of a workpiece held by the holding table; a liquid supply nozzle adapted to supply a liquid to the gap from one side of the liquid chamber; and a liquid discharge nozzle adapted to recover the liquid from the other side of the liquid chamber, to produce a flow of the liquid. A laser beam applying unit includes a condenser adapted to focus a laser beam emitted by a laser oscillator, to apply the laser beam to the workpiece held by the holding table through the transparent plate and the liquid supplied to the gap.

A laser beam applying unit of a laser processing apparatus includes a laser oscillator, a condenser adapted to focus the laser beam emitted from the laser oscillator and apply the laser beam to a workpiece, and a liquid jetting apparatus disposed at a lower end portion of the condenser and adapted to jet a liquid to an upper surface of the workpiece. The liquid jetting apparatus includes: a transparent plate disposed at the lower end portion of the condenser and permitting transmission therethrough of the laser beam; a casing provided with a space defined by a ceiling wall composed of the transparent plate, side walls, and a bottom wall; an opening formed in the bottom plate, extending in a processing feeding direction, and permitting passage therethrough of the laser beam focused by the condenser; and a liquid supply section adapted to supply the liquid to the casing.

A wafer forming method includes a peeling layer forming step of applying, to a SiC ingot, a laser beam of such a wavelength as to be transmitted through the SiC ingot, with a focal point of the laser beam positioned at a depth corresponding to a thickness of a wafer to be formed from a first surface of the SiC ingot, to form a peeling layer including a modified section and cracks; and a wafer forming step of immersing the SiC ingot in a liquid and applying an ultrasonic wave to the SiC ingot through the liquid, to thereby peel a part of the SiC ingot with the peeling layer as an interface and form the wafer. In the wafer forming step, the ultrasonic wave is applied to the SiC ingot while a sweep treatment of regularly varying the oscillation frequency of an ultrasonic vibrator is performed.

A wafer forming method includes a peeling layer forming step of applying, to a SiC ingot, a laser beam of such a wavelength as to be transmitted through the SiC ingot, with a focal point of the laser beam positioned at a depth corresponding to a thickness of a wafer to be formed from a first surface of the SiC ingot, to form a peeling layer including a modified section and cracks; and a wafer forming step of immersing the SiC ingot in a liquid and applying an ultrasonic wave to the SiC ingot through the liquid, to thereby peel a part of the SiC ingot with the peeling layer as an interface and form the wafer. In the wafer forming step, the ultrasonic wave is applied to the SiC ingot while a sweep treatment of regularly varying the oscillation frequency of an ultrasonic vibrator is performed.

Provided is a method for preparing gold nanorods having a high catalytic activity by using a femtosecond laser. The method includes: (1) preparing a gold seed solution; (2) preparing a gold nanorod solution by a seed solution growth process; (3) subjecting the gold nanorod solution to a centrifugal separation to obtain the gold nanorods, and dropping the gold nanorods on a silicon substrate; (4) building a system for preparing the gold nanorods having the high catalytic activity by using the femtosecond laser; and (5) emitting a pulse of the femtosecond laser on the silicon substrate, to allow an electric field distribution of a surface of the gold nanorod on the silicon substrate to change, to partially exfoliate atoms on the surface of the gold nanorod, thereby obtaining the gold nanorod with the high catalytic activity.

A liquid supply mechanism disposed over a holding unit of laser processing apparatus includes a liquid chamber having a circular-disc-shaped transparent plate positioned to form a gap between the circular-disc-shaped transparent plate and an upper surface of the workpiece held by the holding table, a liquid supply nozzle that supplies a liquid from one side of the liquid chamber to the gap, a liquid discharge nozzle that discharges the liquid from the other side of the liquid chamber, and a rotation mechanism that rotates the circular-disc-shaped transparent plate and generates a flow velocity in the liquid supplied to the gap. The laser beam irradiation unit includes a laser oscillator that emits a laser beam and a condenser that condenses the laser beam emitted from the laser oscillator and irradiates the workpiece with the laser beam transmitted through the transparent plate and the liquid supplied to the gap.