High purity AlGaAs from methyl-based precursors using in situ gettering of alkoxides

Roberts, J.S.; David, J.P.R.; Sale, T.E.; Tihanyi, P.

doi:10.1016/0022-0248(94)90048-5

Cited by 15 publications

(4 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Above this field neglecting hot-electron effects would not be justified. A complication, also observed by Hickmott et al [7], was the effect of negative space charge due to the AlGaAs being weakly p-type, caused by the presence of carbon [8], before being compensated by electrons from the contacts. This has the effect of adding to the barrier height, otherwise determined by the band-edge discontinuity minus the Fermi level in the contacts.…”

Section: Introductionmentioning

confidence: 89%

“…The samples, which were selected to clearly illustrate different forms of voltage dependence in the dark-current I -T plots, were grown by MOVPE on a doped substrate [8]. They contained a doped n + GaAs contact layer, a nominally undoped Al x Ga 1−x As barrier with graded interfaces and an n + GaAs contact layer.…”

Section: Methodsmentioning

confidence: 99%

“…The band structure, where φ b is the bandgap discontinuity and φ f is the Fermi level, is shown for a structure with 10 wells in figure 1. A low background concentration of carbon and oxygen in the AlGaAs was realized using a growth temperature of 600 • C and processing the metalorganic precursors using reactive metals dissolved in gallium [8]. The residual p-type background doping in the AlGaAs is due to the presence of carbon.…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

The effect of quantum wells on electron transport across GaAs/AlGaAs graded barrier structures

Bishop

Daniels

Ridley

et al. 1996

Semicond. Sci. Technol.

View full text Add to dashboard Cite

Electron transport over short n + GaAs/Al x Ga 1−x As/n + GaAs barrier structures containing doped GaAs quantum wells has been investigated. The barriers had graded interfaces at the contacts which inhibited tunnelling at low electric fields. It was found that the presence of wells pinned the Fermi level, eliminating the increase in the barrier height caused by background space charge seen in AlGaAs barriers. The wells also had the effect of magnifying any injected space charge, which meant that the electric field was non-uniform across the sample. Hence the three regions, graded interface/central region with wells/graded interface, functioned like three resistors in series and this behaviour has been modelled successfully using drift-diffusion theory. Increasing the density of wells, which allows tunnelling to occur at lower fields and higher temperatures, limits the range over which the thermionic current dominates.

show abstract

Section: Introductionmentioning

confidence: 89%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

The effect of quantum wells on electron transport across GaAs/AlGaAs graded barrier structures

Bishop

Daniels

Ridley

et al. 1996

Semicond. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…Low temperature growth of AIGaAs promotes contamination by oxygen, however, technological improvements have been made which enable good quality material to be grown at low temperatures [3,4]. In addition to providing sources at wavelengths useful for applications such as photodynaniic therapy, the larger thermal conductivity of AlGaAs compared with AIGaInP may make the Ga,In1As/AlGaAs system competitive for applications requiring high output power at wavelengths shorter than 700nxn.…”

Section: Introductionmentioning

confidence: 99%

Al x GayIn 1-x-y As/AlGaAs quantum well lasers at 670 to 750 nm

Smowton

Blood

Mogensen³

et al. 1997

In-Plane Semiconductor Lasers: From Ultraviolet to Midinfrared

View full text Add to dashboard Cite

quantum well lasers offer the prospect of devices at intermediate wavelengths between about 690mn and l5Onin with applications in areas such as photodynamic therapy. The larger thermal conductivity of A1GaAS compared to that of A1GaInP could make the A1XGa)InlAs systeni attractive for high power devices. The incorporation of indium in the quantum well also improves material quality and introduces compressive strain which enhances the intrinsic perfonnance beyond that of the phosphide system due to the larger spin orbit splitting and more similar electron and hole density ofstates in Ga,ln1.As compared with Ga,In1P.We have modelled the gain and radiative recombination of wells with AI.45Gao55M barriers at a wavelength in the region 720 to 730nm. This shows that the intrinsic gain-current characteristic is superior to that of an idealised GaInP/AIGaJnP laser at the same wavelength. Devices have been fabricated, which operate at 685nmand 75Onni at room temperature, and the length dependence of the threshold current, measured as a function of temperature between 140K and 400K, analysed. At the shorter wavelength the room temperature threshold current is dominated by thennally activated carrier loss from the well. Although this could be reduced by further opthnisation, short wavelength operation is severely resthcted by the band gap of the A1GaAS barriers and this material system will be of greatest benefit for devices at wavelengths greater than about 7lOnm.

show abstract

MOVPE of III–V Compounds

Jones¹,

O’Brien

1997

CVD of Compound Semiconductors

View full text Add to dashboard Cite

High purity AlGaAs from methyl-based precursors using in situ gettering of alkoxides

Cited by 15 publications

References 7 publications

The effect of quantum wells on electron transport across GaAs/AlGaAs graded barrier structures

The effect of quantum wells on electron transport across GaAs/AlGaAs graded barrier structures

Al x GayIn 1-x-y As/AlGaAs quantum well lasers at 670 to 750 nm

MOVPE of III–V Compounds

Contact Info

Product

Resources

About