ebl structure
DESCRIPTION
EBL Structure. Structure 1. N-EBL. Barrier. Well. Al0.17Ga0.83 Al0.25Ga0.75 Al0.17Ga0.83. Structure 2. P -EBL. P-Barrier. P-Barrier. P-Barrier. Well. Structure 3. P -EBL. N-EBL. P-Barrier. P-Barrier. P-Barrier. Well. Structure 4. 20nm Al 0.2 Ga 0.8 N. - PowerPoint PPT PresentationTRANSCRIPT
1
EBL Structure
2
N-EBL
Barrier
Well
Al0.17Ga0.83 Al0.25Ga0.75 Al0.17Ga0.83
Structure 1
3
Well
P-EBL
P-Barrier
Structure 2
P-Barrier P-Barrier
4
Well
P-EBL
P-BarrierN-EBL
Structure 3
P-Barrier P-Barrier
5
p-GaN
p-EBL
GaNInGaN
20nm Al0.2Ga0.8N
2nm Al0.05Ga0.95N
Structure 4
6
n-GaN
Superlattice n-EBL Al0.1Ga0.9N/GaN3nm/1nm 5pair
MQW
Al0.2Ga0.8N 5nmStructure 5
7
p-GaN
p-EBL
GaNInGaN
20nm Al 含量 0%~25%~0%
Structure 6
8
p-GaNn-GaN
p-AlGaN
MQW(GaN/InGaN)
Original structure
p-GaNn-GaN
p-AlGaN
MQW(GaN/InGaN)
New structure
透過在 MQW 與 EBL 間插入一層 AlGaN superlattice ,做為緩衝 last barrier 與 EBL lattice mismatch 所帶來能帶傾斜的效應 !! 進而增加 EBL有效的能障高度…
Structure 7
9
p-GaNn-GaN
p-AlGaN
MQW(GaN/InGaN)
Original structure
在 last barrier 做一 n 參雜,目的在於形成一空乏區內建電場 ! 透過 PN 面空乏區電場來去抵補極化場 !!
n-GaN
New structure
p-GaN
p-type
n-type
Structure 8
10
極化場方向
內建電場方向
11
p-GaNn-GaN
p-AlGaN
MQW(GaN/InGaN)
Original structure
n-GaN
New structure A p-type
MQW(InGaN/InGaN)
Graded-GaN
InGaN barrier
GaN+last barrier
EBL
在 QW 中使用 InGaN/InGaN,增加晶格與晶格間的長晶匹配並在最後 Last barrier 處 做一 GaN 的能帶調變,目的在改善與最後的 Al-GaN 晶格missmatch!! 藉此改善 晶格間的極化效應。
Structure 9
12
n-GaN
New structure B p-type
MQW(InGaN/InGaN)
Graded P-GaN
InGaN barrier
P-GaN+last barrier
EBL
13
n-GaN
New structure C p-type
MQW(InGaN/InGaN)
Graded P-GaN
InGaN barrier
P-GaN+last barrier
EBL
SuperLattice
14
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