Abstract:
A method for forming a PN junction in graphene includes: forming a graphene layer, and forming a DNA molecule layer on a partial region of the graphene layer, the DNA molecule layer having a nucleotide sequence structure designed to provide the graphene layer with a predetermined doping property upon adsorption on the graphene layer. The DNA molecule has a nucleotide sequence structure designed for doping of graphene so that doped graphene has a specific semiconductor property. The DNA molecule is coated on the surface of the graphene layer of which the partial region is exposed by micro patterning, and thereby, PN junctions of various structures may be formed by a region coated with the DNA molecule and a non-coated region in the graphene layer.
Abstract:
Disclosed herein is a single pulse laser apparatus that includes: a resonator having a first mirror, a second mirror, a gain medium, an electro-optic modulator (EOM) configured to perform single pulse switching, and an acousto-optic modulator (AOM) configured to perform mode-locking; a photodiode configured to measure a laser beam oscillated in the resonator; a synchronizer configured to convert an electrical signal, which is generated by measuring the laser beam, into a transistor-transistor logic (TTL) signal; a delay unit configured to set a delay time for the TTL signal to synchronize the EOM and the AOM and output a trigger TTL signal according to the delay time; an AOM driver configured to input the trigger TTL signal to the AOM that performs mode-locking and drive the AOM; and an EOM driver configured to input the trigger TTL signal to the EOM that performs single pulse switching and drive the EOM.
Abstract:
There are provided a fabricating method of a carbon nanotube-based field effect transistor having an improved binding force with a substrate and a carbon nanotube-based field effect transistor fabricated by the fabricating method. The method includes forming an oxide film on a substrate, forming a photoresist pattern on the oxide film, forming a metal film on the entire surface of the oxide film having the photoresist pattern, removing the photoresist by lifting off, adsorbing carbon nanotubes on the substrate from which the photoresist is removed, performing an annealing process to the substrate to which the carbon nanotubes are adsorbed, and removing the metal film. Since an adhesive strength between a substrate and carbon nanotubes increases, stability and reliability of a field effect transistor can be improved. If the field effect transistor is applied to a liquid sensor or the like, a lifespan of the sensor can be extended and reliability of a measurement result obtained by the sensor can be improved.
Abstract:
An apparatus for measuring ganglion cells may include: a light generation unit configured to irradiate a first light signal polarized in a first direction and a second light signal polarized in a second direction perpendicular to the first direction to a subject; a reflected light processing unit configured to generate an amplification signal corresponding to an image of the subject using a first reflection signal, which is the first light signal reflected from the subject, and a second reflection signal, which is the second light signal reflected from the subject; and an image processing unit configured to measure ganglion cells in the subject using the amplification signal. The apparatus may be used to count the number of normal ganglion cells in the retina by measuring a phase difference of two lights polarized in different directions. The apparatus may also be used to monitor the progress of glaucoma.
Abstract:
Provided is an extreme ultra-violet (EUV) beam generation apparatus using multi-gas cell modules in which a gas is prevented from directly flowing into a vacuum chamber by adding an auxiliary gas cell serving as a buffer chamber to a main gas cell, a diffusion rate of the gas is decreased, a high vacuum state is maintained, and a higher power EUV beam is continuously generated.
Abstract:
Provided are an apparatus and method for calibrating an extreme ultraviolet (EUV) spectrometer in which a wavelength of a spectrum of EUV light used for EUV lithography and mask inspection technology can be measured accurately.
Abstract:
Provided is a pulse laser apparatus for generating laser light. The apparatus includes a first mirror and a second mirror which are disposed at both ends of a resonator and configured to reflect the laser light, a gain medium disposed between the first and second mirrors and configured to amplify and output light incident from an outside, an etalon configured to adjust a pulse width of the laser light, and an acousto-optic modulator disposed between the first and second mirrors and configured to form a mode-locked and Q-switched signal from the laser light, in which some of the laser light is output through either the first or second mirror to outside the resonator.
Abstract:
A photoluminescence wavelength tunable material may include a composite including a graphene oxide layer and metal nanoparticles attached on the graphene oxide layer. By attaching the metal nanoparticles to the graphene oxide, the photoluminescence wavelength (i.e., the color of emitted light) of the graphene oxide may be tuned while maintaining the structure and physical properties of graphene oxide. The photoluminescence wavelength tunable material may be applied to an energy harvesting device such as a solar cell which exhibits high efficiency with less loss of light.
Abstract:
Provided is a cell-level retinal disease detection apparatus including a light imaging means configured to emit light to an eyeball and a light processing means which receives light reflected by the eyeball and processes and compensates light for an astigmatism aberration thereof which occurs at the eyeball to compensate. Here, the light processing means includes a wavefront sensor which senses the astigmatism aberration of the reflected light which occurs due to the eyeball and a light compensation mirror which compensates the light based on the sensed astigmatism aberration, and compensates for a difference in the astigmatism aberration to detect a disease of a retina of the eyeball.
Abstract:
Provided is a single pulse laser apparatus. The apparatus including a resonator having a first mirror, a second mirror, a gain medium, and electro-optic modulators (EOMs) which perform each mode-locking and Q-switching, the apparatus includes a photodiode which measures laser light that oscillates from the resonator, a synchronizer which converts an electrical signal generated by measuring the laser light into a transistor-transistor logic (TTL) signal, a delay unit which sets a latency determined in order to synchronize a mode-locked pulse with a Q-switched pulse to the TTL signal, and outputs a trigger TTL signal according to the latency, and a Q-driver which inputs the trigger TTL signal to the EOM which performs Q-switching, and causes the EOM to operates.