High Electron Mobility Transistor (HEMT) Flament Benjamin.
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Transcript of High Electron Mobility Transistor (HEMT) Flament Benjamin.
![Page 1: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/1.jpg)
High Electron Mobility Transistor (HEMT)
Flament Benjamin
![Page 2: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/2.jpg)
PLAN
•Presentation
•Fabrication
![Page 3: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/3.jpg)
Presentation
• 1980 at Fujitsu
• TEGFET, MODFET, HFET
• Goal->transportation in a doped material
![Page 4: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/4.jpg)
• Heterojunction: 2 layers
– Highly doped layer with grand gap
– Non-doped layer with small gap
Presentation
![Page 5: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/5.jpg)
![Page 6: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/6.jpg)
Source
Gate
Drain
CAP small doped gap CAP small doped gap
Schottky contact grand gap non doped
Carrier donor layer grand gap doped
Spacer grand gap non doped
Canal small gap non doped
Buffer grand gap non doped
Substrat
![Page 7: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/7.jpg)
PLAN
•Presentation
•Fabrication
![Page 8: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/8.jpg)
Plan
•Cleaning
•Deposition, MBE
•Ohmic contacts
![Page 9: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/9.jpg)
Fabrication
• Cleaning of the wafer
– GaAs wafer->more complicated than Si wafer– Difficulties to remove the oxide of Ga and As– We use the electron cyclotron resonance
(ECR)
![Page 10: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/10.jpg)
Fabrication
• As oxide is removed by heating and :
x=1, 3, 5 stands for the various oxides of arsenic
• Ga oxide is removed by:
)2
1(2 4222 AsAsOxHxHOAs x
OHOGaHOGa 2232 24
![Page 11: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/11.jpg)
Fabrication
• Becomes volatile at 200°C so we choose a
temperature of 400°C
OGa2
![Page 12: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/12.jpg)
Fabrication
• We grow the different layer by molecular beam epitaxy (MBE)
![Page 13: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/13.jpg)
![Page 14: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/14.jpg)
30 periods of AlGaAs/GaAs superlattice buffer Buffer grand gap non doped
Substrat
30 periods of AlGaAs/GaAs superlattice buffer
![Page 15: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/15.jpg)
Canal small gap non doped
Buffer grand gap non doped
Substrat
120 Å of In(0.2)Ga(0.8)As
![Page 16: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/16.jpg)
Spacer grand gap non doped
Canal small gap non doped
Buffer grand gap non doped
Substrat
35 Å of Al(0.23)Ga(0.77)As
![Page 17: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/17.jpg)
Carrier donor layer grand gap doped
Spacer grand gap non doped
Canal small gap non doped
Buffer grand gap non doped
Substrat
![Page 18: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/18.jpg)
Schottky contact grand gap non doped
Carrier donor layer grand gap doped
Spacer grand gap non doped
Canal small gap non doped
Buffer grand gap non doped
Substrat
250 Å of Al(0.23)Ga(0.77)As
![Page 19: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/19.jpg)
Fabrication
photoresist
Wafer and others layers
![Page 20: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/20.jpg)
Fabrication
Photoresist
Wafer and others layers
Mask
![Page 21: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/21.jpg)
Fabrication
photoresist
Mask
![Page 22: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/22.jpg)
Fabrication
metal
metal GaAs metal
GaAs photoresist GaAs
Layers
![Page 23: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/23.jpg)
Source Drain
CAP small doped gap CAP small doped gap
Schottky contact grand gap non doped
Carrier donor layer grand gap doped
Spacer grand gap non doped
Canal small gap non doped
Buffer grand gap non doped
Substrat
![Page 24: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/24.jpg)
Fabrication
• 3 layers:– PPMA for the bottom layer– PMIPK for the middle layer– PPMA for the top layer
• PPMA(polypropylmethacrylate)
• PMIPK(polymethylisopropenylketone)
![Page 25: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/25.jpg)
Fabrication
• Using deep UV lithography
![Page 26: High Electron Mobility Transistor (HEMT) Flament Benjamin.](https://reader036.fdocuments.in/reader036/viewer/2022081421/56649f2f5503460f94c49f00/html5/thumbnails/26.jpg)
Research
• Lattice matching