Electronics and Telecommunications Research Institute

Mun-Cheol Paek

Kyoung-Ik Cho

Sung-Yool Choi

Jeen Hur

Gi-Pyung Han

Hojun Ryu

Hyeon-Bong Pyo

Dong Woo Suh

Yongwoo Park

Kyu-Hwan Shim

Yeungjoon Sohn

Provided is a focusing waveguide grating coupler using a leaky mode which can form single output beam while relieving the dependency on manufacturing processes. The focusing waveguide grating coupler of the present research includes: a substrate having a first refraction index n1; a first core layer having a second refraction index n2, the first core layer being formed on the substrate; a second core layer having a third refraction index n3, the second core layer being formed on the first core layer apart from the first core layer with a space d in between; a first cladding layer having a fourth refraction index n4, the first cladding layer being formed on the second core layer; a second cladding layer having a fifth refraction index n5, the second cladding layer being formed on the first cladding layer and inserted between the first core layer and the second core layer; and a Fresnel lens positioned on the second cladding layer, wherein the refractive indexes satisfy conditions of n5&#x3e;(n2, n3)&#x3e;n1 and n5&#x3e;n4; and light inputted through the first and second core layers to the Fresnel lens as radiated leaky beam by a leaky mode formed according to the conditions, and the leaky beam forms an optical focus by performing single directional coupling.

Highly efficient focusing waveguide grating coupler using leaky mode

A triode-type field emission device includes an insulating substrate; a cathode formed on the insulating substrate; a field emitter aligned on the cathode, wherein the field emitter includes a plurality of emitter tips and each emitter tip has the diameter of nanometers; an insulating layer positioned around the field emitter for electrically isolating the field emitter; and a gate electrode formed on the insulating layer, wherein the gate electrode is closed to an upper portion of the field emitter. Therefore, the triode-type field emission device may be operable in a low voltage.

Triode-type field emission device having field emitter composed of emitter tips with diameter of nanometers and method for fabricating the same

The object of the present invention is to provide a RF induction plasma source generating apparatus which generates a stabilized plasma and sustains the stabilized plasma by maintaining the plasma pressure from several hundreds Torr to several thousands Torr with attachment a buffer nozzle cap, upper metallic blocking films and lower metallic blocking films to a nozzle cap, plasma tube and RF induction coils, respectively for separating the plasma source generating apparatus from the chamber. To accomplish the object of the invention, the plasma source generating apparatus comprising PBN tube, RF induction coils, a nozzle, and a nozzle cap is characterized by a buffer nozzle cap for locating between the nozzle cap and the plasma tube and modulating the flow of the gas to modulate the difference between the chamber pressure and the plasma pressure; sealing films formed by sealing the lips of the buffer nozzle cap, the nozzle cap and the plasma tube for preventing the leakage of gas; and upper blocking films and lower blocking films for blocking the spread out of the RF electric field induced in the RF induction coils and converging the plasma source.

RF induction plasma source generating apparatus

Growing community of inventors

Taejon, South Korea

Mun-Cheol Paek