Unusually high-density 2D electron gases in N-polar AlGaN/GaN heterostructures with GaN/AlN superlattice back barriers grown on sapphire substrates | Matter42 Literature

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Unusually high-density 2D electron gases in N-polar AlGaN/GaN heterostructures with GaN/AlN superlattice back barriers grown on sapphire substrates | Matter42 Literature

Materials

AlGaN/GaN heterostructure

AlGaN/GaN

Studied Material

Also known as

N-polar AlGaN/GaN heterostructure

Variables

polarity= N-polar

studied material

GaN

GaN

Studied Material

Also known as

GaN bufferGaN channelGaN cap

studied material

AlN

AlN

Studied Material

Also known as

AlN barrierAlN in superlattice

studied material

Al0.3Ga0.7N

Al0.3Ga0.7N

Studied Material

Also known as

Al0.3Ga0.7N barrier

Variables

al_fraction= 0.3

studied material

Al0.4Ga0.6N

Al0.4Ga0.6N

Studied Material

Also known as

Al0.4Ga0.6N cap

Variables

al_fraction= 0.4

studied material

sapphire

Al₂O₃

Substrate / Dielectric

Also known as

(0001) sapphire

Variables

orientation= (0001)

miscut_toward= a-sapphire-plane

miscut_angle_deg= 4

substrate or dielectric

trimethylgallium

TMGa

Precursor

Also known as

TMGa

precursor

trimethylaluminum

TMAl

Precursor

Also known as

TMAl

precursor

ammonia

NH₃

Precursor

Also known as

ammonia

precursor

aluminum-titanium

Al/Ti

Capping Or Contact

Also known as

Al-Ti Ohmic contactsaluminum-titanium Ohmic contacts

capping or contact

Growth

MOCVD — metal-organic chemical vapor deposition

MOCVD

vapor-phase deposition

Parameters

Temperature1025°C

Pressure20 kPa

Flow Rate—

Growth Time—

Ramp Rate

Characterization

Transport

TransportExperimental

Conditions

contactsaluminum-titanium Ohmic contacts

magnetic field T1

measurement temperatureroom temperature

Figure References

Properties

Type	Label	Value	Material	Sample	Condition	Source
Fet Carrier Concentration	2DEG density	30000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Fet Mobility	electron mobility	440cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Fet Carrier Concentration	2DEG density	140000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Mobility	electron mobility	169cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Sheet Resistance	Hall sheet resistance	264ohm/sq	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Carrier Concentration	2DEG density	16000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Fet Mobility	electron mobility	80cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Fet Sheet Resistance	contactless sheet resistance	710ohm/sq	AlGaN/GaN	Control sample: 4-period GaN/AlN superlattice on GaN buffer		—
Surface Roughness	RMS roughness	4.2nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Surface Roughness	RMS roughness	4.5nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Surface Roughness	RMS roughness	8.5nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Composition Fraction	SL barrier composition inference	high Al-content AlGaN rather than pure AlN	AlN	Control sample: 4-period GaN/AlN superlattice on GaN buffer		—
PL Peak	regex-detected PL peak	400nm	—	—	—	—

Simulations

Other Computational

TCAD band-diagram and polarization-charge simulations; electrostatic modeling of heterostructure electron density.Technology Computer Aided Design (TCAD)

Settings

structure modeheterostructure

modeled quantityband diagram and electron density

species includedpolarization charge

comparison sample

Materials

AlGaN/GaN heterostructure

AlGaN/GaN

Studied Material

Also known as

N-polar AlGaN/GaN heterostructure

Variables

polarity= N-polar

studied material

GaN

GaN

Studied Material

Also known as

GaN bufferGaN channelGaN cap

studied material

AlN

AlN

Studied Material

Also known as

AlN barrierAlN in superlattice

studied material

Al0.3Ga0.7N

Al0.3Ga0.7N

Studied Material

Also known as

Al0.3Ga0.7N barrier

Variables

al_fraction= 0.3

studied material

Al0.4Ga0.6N

Al0.4Ga0.6N

Studied Material

Also known as

Al0.4Ga0.6N cap

Variables

al_fraction= 0.4

studied material

sapphire

Al₂O₃

Substrate / Dielectric

Also known as

(0001) sapphire

Variables

orientation= (0001)

miscut_toward= a-sapphire-plane

miscut_angle_deg= 4

substrate or dielectric

trimethylgallium

TMGa

Precursor

Also known as

TMGa

precursor

trimethylaluminum

TMAl

Precursor

Also known as

TMAl

precursor

ammonia

NH₃

Precursor

Also known as

ammonia

precursor

aluminum-titanium

Al/Ti

Capping Or Contact

Also known as

Al-Ti Ohmic contactsaluminum-titanium Ohmic contacts

capping or contact

Growth

MOCVD — metal-organic chemical vapor deposition

MOCVD

vapor-phase deposition

Parameters

Temperature1025°C

Pressure20 kPa

Flow Rate—

Growth Time—

Ramp Rate

Characterization

Transport

TransportExperimental

Conditions

contactsaluminum-titanium Ohmic contacts

magnetic field T1

measurement temperatureroom temperature

Figure References

Properties

Type	Label	Value	Material	Sample	Condition	Source
Fet Carrier Concentration	2DEG density	30000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Fet Mobility	electron mobility	440cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Fet Carrier Concentration	2DEG density	140000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Mobility	electron mobility	169cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Sheet Resistance	Hall sheet resistance	264ohm/sq	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Carrier Concentration	2DEG density	16000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Fet Mobility	electron mobility	80cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Fet Sheet Resistance	contactless sheet resistance	710ohm/sq	AlGaN/GaN	Control sample: 4-period GaN/AlN superlattice on GaN buffer		—
Surface Roughness	RMS roughness	4.2nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Surface Roughness	RMS roughness	4.5nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Surface Roughness	RMS roughness	8.5nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Composition Fraction	SL barrier composition inference	high Al-content AlGaN rather than pure AlN	AlN	Control sample: 4-period GaN/AlN superlattice on GaN buffer		—
PL Peak	regex-detected PL peak	400nm	—	—	—	—

Simulations

Other Computational

TCAD band-diagram and polarization-charge simulations; electrostatic modeling of heterostructure electron density.Technology Computer Aided Design (TCAD)

Settings

structure modeheterostructure

modeled quantityband diagram and electron density

species includedpolarization charge

comparison sample

Materials

AlGaN/GaN heterostructure

AlGaN/GaN

Studied Material

Also known as

N-polar AlGaN/GaN heterostructure

Variables

polarity= N-polar

studied material

GaN

GaN

Studied Material

Also known as

GaN bufferGaN channelGaN cap

studied material

AlN

AlN

Studied Material

Also known as

AlN barrierAlN in superlattice

studied material

Al0.3Ga0.7N

Al0.3Ga0.7N

Studied Material

Also known as

Al0.3Ga0.7N barrier

Variables

al_fraction= 0.3

studied material

Al0.4Ga0.6N

Al0.4Ga0.6N

Studied Material

Also known as

Al0.4Ga0.6N cap

Variables

al_fraction= 0.4

studied material

sapphire

Al₂O₃

Substrate / Dielectric

Also known as

(0001) sapphire

Variables

orientation= (0001)

miscut_toward= a-sapphire-plane

miscut_angle_deg= 4

substrate or dielectric

trimethylgallium

TMGa

Precursor

Also known as

TMGa

precursor

trimethylaluminum

TMAl

Precursor

Also known as

TMAl

precursor

ammonia

NH₃

Precursor

Also known as

ammonia

precursor

aluminum-titanium

Al/Ti

Capping Or Contact

Also known as

Al-Ti Ohmic contactsaluminum-titanium Ohmic contacts

capping or contact

Growth

MOCVD — metal-organic chemical vapor deposition

MOCVD

vapor-phase deposition

Parameters

Temperature1025°C

Pressure20 kPa

Flow Rate—

Growth Time—

Ramp Rate

Characterization

Transport

TransportExperimental

Conditions

contactsaluminum-titanium Ohmic contacts

magnetic field T1

measurement temperatureroom temperature

Figure References

Properties

Type	Label	Value	Material	Sample	Condition	Source
Fet Carrier Concentration	2DEG density	30000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Fet Mobility	electron mobility	440cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Fet Carrier Concentration	2DEG density	140000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Mobility	electron mobility	169cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Sheet Resistance	Hall sheet resistance	264ohm/sq	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Carrier Concentration	2DEG density	16000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Fet Mobility	electron mobility	80cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Fet Sheet Resistance	contactless sheet resistance	710ohm/sq	AlGaN/GaN	Control sample: 4-period GaN/AlN superlattice on GaN buffer		—
Surface Roughness	RMS roughness	4.2nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Surface Roughness	RMS roughness	4.5nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Surface Roughness	RMS roughness	8.5nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Composition Fraction	SL barrier composition inference	high Al-content AlGaN rather than pure AlN	AlN	Control sample: 4-period GaN/AlN superlattice on GaN buffer		—
PL Peak	regex-detected PL peak	400nm	—	—	—	—

Simulations

Other Computational

TCAD band-diagram and polarization-charge simulations; electrostatic modeling of heterostructure electron density.Technology Computer Aided Design (TCAD)

Settings

structure modeheterostructure

modeled quantityband diagram and electron density

species includedpolarization charge

comparison sample

Materials

AlGaN/GaN heterostructure

AlGaN/GaN

Studied Material

Also known as

N-polar AlGaN/GaN heterostructure

Variables

polarity= N-polar

studied material

GaN

GaN

Studied Material

Also known as

GaN bufferGaN channelGaN cap

studied material

AlN

AlN

Studied Material

Also known as

AlN barrierAlN in superlattice

studied material

Al0.3Ga0.7N

Al0.3Ga0.7N

Studied Material

Also known as

Al0.3Ga0.7N barrier

Variables

al_fraction= 0.3

studied material

Al0.4Ga0.6N

Al0.4Ga0.6N

Studied Material

Also known as

Al0.4Ga0.6N cap

Variables

al_fraction= 0.4

studied material

sapphire

Al₂O₃

Substrate / Dielectric

Also known as

(0001) sapphire

Variables

orientation= (0001)

miscut_toward= a-sapphire-plane

miscut_angle_deg= 4

substrate or dielectric

trimethylgallium

TMGa

Precursor

Also known as

TMGa

precursor

trimethylaluminum

TMAl

Precursor

Also known as

TMAl

precursor

ammonia

NH₃

Precursor

Also known as

ammonia

precursor

aluminum-titanium

Al/Ti

Capping Or Contact

Also known as

Al-Ti Ohmic contactsaluminum-titanium Ohmic contacts

capping or contact

Growth

MOCVD — metal-organic chemical vapor deposition

MOCVD

vapor-phase deposition

Parameters

Temperature1025°C

Pressure20 kPa

Flow Rate—

Growth Time—

Ramp Rate

Characterization

Transport

TransportExperimental

Conditions

contactsaluminum-titanium Ohmic contacts

magnetic field T1

measurement temperatureroom temperature

Figure References

Properties

Type	Label	Value	Material	Sample	Condition	Source
Fet Carrier Concentration	2DEG density	30000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Fet Mobility	electron mobility	440cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Fet Carrier Concentration	2DEG density	140000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Mobility	electron mobility	169cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Sheet Resistance	Hall sheet resistance	264ohm/sq	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Fet Carrier Concentration	2DEG density	16000000000000cm⁻²	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Fet Mobility	electron mobility	80cm²/Vs	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Fet Sheet Resistance	contactless sheet resistance	710ohm/sq	AlGaN/GaN	Control sample: 4-period GaN/AlN superlattice on GaN buffer		—
Surface Roughness	RMS roughness	4.2nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 0-period		—
Surface Roughness	RMS roughness	4.5nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 4-period		—
Surface Roughness	RMS roughness	8.5nm	AlGaN/GaN	N-polar AlGaN/GaN heterostructure on sapphire with 8-period		—
Composition Fraction	SL barrier composition inference	high Al-content AlGaN rather than pure AlN	AlN	Control sample: 4-period GaN/AlN superlattice on GaN buffer		—
PL Peak	regex-detected PL peak	400nm	—	—	—	—

Simulations

Other Computational

TCAD band-diagram and polarization-charge simulations; electrostatic modeling of heterostructure electron density.Technology Computer Aided Design (TCAD)

Settings

structure modeheterostructure

modeled quantityband diagram and electron density

species includedpolarization charge

comparison sample