structure is very simple, but the problem of this structure is low efficiency and organic material(phospors).
③ Red, Green, and Blue LEDs for White Light Illumination
This LED application is structured by three chip(red, green, blue). Each chip emits three color. This structure has more strong light intensity than single chip WLED, but process is too complicate and not cost effective. An
Structural Properties
Fig.1. presents cross-sectional FE-SEM images of all the samples. For all the samples, the columnar shaped ZnO grains grown normal to the substrate surface are clearly seen. When MZO and GZO films are deposited after ZnO films, it seems that similar columnar shaped grains are formed. It can indicate if the same conditions are preserved, all films can be grownvertically. I
The crystal structure is a member of the hexagonal crystal system and consists of tetrahedrally coordinated Zinc and Sulfur atoms that are stacked in an ABABAB pattern.
The structure is closely related to the structure of lonsdaleite, or hexagonal diamond.
As there all orientations of the crystal, rings of different 2θ values are formed
A single crystal specimen in a Bragg-Brentano diffrac
Partial substitution of Ba by a smaller M2+ ion
unit cell volume decreases and the phase transition temperature decreases
An insulator at room temperature becomes semiconductive after doping
trivalent donars (e.g. La, Sb, Y) substitute for the Ba2+
pentavalent donars (e.g. Sb, Nb, Ta) substitute for Ti4+.
와인 보관 창고
적정온도 : 7-13도
더 낮은
material + conducting material + binder
LiCoO2
carbon PVDF
Counter electrode & reference electrode : lithium foil
Electrolyte : Li salt IN non-aqueous solvent
Li salt : LiPF6, LiBF4, LiClO4…
Solvent : EC, PC, DMC, DME…
Lab. of Energy Conversion & STORAGE Materials
Fig. (a) Typical discharge
curve of LiCoO2 AND its
(b,c) lattice parameter
CHANGE
Light Emitting Diode(LED) Process Design
- Team Project Report(Group12)
Ⅰ. INTRODUCTION
Ⅰ. LED
LED(Light Emitting Diode)는 반도체에 전압을 인가할 때 생기는 발광현상을 이용한 광원이다. 전기를 통해주면 전자가 에너지 레벨이 높은 곳에서 낮은 곳으로 이동하면서 특정한 파장의 빛을 내는 화합물 반도체에
물리적 접근이란 말 그대로 정보시스템 자산을 물리적으로 접근하는 것을 말한다. 이러한 물리적 접근이 가능한 정보시스템 자산에는 데이터, 응용, 하드웨어, 시설/설비 등이 포함된다. 불법적인 물리적 접근은 네 가지 유형의 손실을 모두 발생시킬 수 있다.
논리적 접근이란 정보시스템 자산을
1) 나노 슈퍼구조체 : 기존 자성 메모리보다 데이터 저장용량이 10배 이상 향상된
차세대 초고집적 나노 저장 매체가 개발됐다. 지름 20㎚의 나노입자 125조개를 1㎣ 부피의 공간에 집적시킨 ‘3차원 네트워크 나노 슈퍼구조체(nano-super-lattice structure)’를
개발했다. 개발한 3차원 나노 슈퍼 구조체는 나
structure of MgO is different from that of ZnO
- MgO : rock-salt cubic structure. ZnO : wurtzite hexagonal structure.
The different crystal structure induces the lattice mismatch
When MgxZn1−xO becomes a metastable alloy, it is expected that the exchange between the ions is easy and the solubility will increase
- because the ionic radii of Mg and Zn atoms are similar
MgxZn1&