Surface Alteration of Planar P-Type Gallium Nitride to Porous Structure Using 50 Hz Alternating Current-Assisted Photo-Electrochemical Etching Route

AbstractWhen the stoichiometric TiN was deposited directly on GaN, we obtained columnar TiN grains of 5-20 nm section which cross the whole film thickness and are rotated mostly around the [111] axis. The conventional epitaxial relationship is obtained and no amorphous patches are observed at the interface. The deposition of TiN on Si doped GaN layers lead to the formation of an ohmic contact, whereas we obtain a rectifying contact on p type layers.

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Structural, Surface Morphological and Photoluminescence Properties of Nanostructured Porous Silicon Material for Optoelectronics Application

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.584.290 ◽

2012 ◽

Vol 584 ◽

pp. 290-294 ◽

Cited By ~ 1

Author(s):

Jeyaprakash Pandiarajan ◽

Natarajan Jeyakumaran ◽

Natarajan Prithivikumaran

Keyword(s):

Porous Silicon ◽

Current Density ◽

Light Emission ◽

Electrochemical Etching ◽

Light Emitting Diode ◽

Radiative Transition ◽

Sem Images ◽

Optoelectronic Application ◽

Gap Opening ◽

P Type

The promotion of silicon (Si) from being the key material for microelectronics to an interesting material for optoelectronic application is a consequence of the possibility to reduce its device dimensionally by a cheap and easy technique. In fact, electrochemical etching of Si under controlled conditions leads to the formation of nanocrystalline porous silicon (PS) where quantum confinement of photo excited carriers and surface species yield to a band gap opening and an increased radiative transition rate resulting in efficient light emission. In the present study, the nanostructured PS samples were prepared using anodic etching of p-type silicon. The effect of current density on structural and optical properties of PS, has been investigated. XRD studies confirm the presence of silicon nanocrystallites in the PS structure. By increasing the current density, the average estimated values of grain size are found to be decreased. SEM images indicate that the pores are surrounded by a thick columnar network of silicon walls. The observed PL spectra at room temperature for all the current densities confirm the formation of PS structures with nanocrystalline features. PL studies reveal that there is a prominent visible emission peak at 606 nm. The obtained variation of intensity in PL emission may be used for intensity varied light emitting diode applications. These studies confirm that the PS is a versatile material with potential for optoelectronics application.

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A Monolithic White-Light LED Based on GaN Doped with Be

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.93.264 ◽

2014 ◽

Vol 93 ◽

pp. 264-269 ◽

Cited By ~ 1

Author(s):

Henryk Teisseyre ◽

Michal Bockowski ◽

Toby David Young ◽

Szymon Grzanka ◽

Yaroslav Zhydachevskii ◽

...

Keyword(s):

Gallium Nitride ◽

White Light ◽

Light Emission ◽

Light Emitting Diode ◽

Yellow Emission ◽

Bulk Crystals ◽

Light Emitting ◽

Type Conductivity ◽

P Type ◽

Colour Rendering

In this communication, the use of gallium nitride doped with beryllium as an efficient converter for white light emitting diode is proposed. Until now beryllium in this material was mostly studied as a potential p-type dopant. Unfortunately, the realization of p-type conductivity in such a way seems impossible. However, due to a very intensive yellow emission, bulk crystals doped with beryllium can be used as light converters. In this communication, it is demonstrated that realisation of such diode is possible and realisation of a colour rendering index is close to that necessary for white light emission.

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Magnesium doped semipolar (11–22) p-type gallium nitride: Impact of dopant concentration variants towards grain size distributions and crystalline quality

Thin Solid Films ◽

10.1016/j.tsf.2021.139003 ◽

2021 ◽

pp. 139003

Author(s):

Omar Al-Zuhairi ◽

Afiq Anuar ◽

Abdullah Haaziq Ahmad Makinudin ◽

Ahmad Shuhaimi Abu Bakar ◽

M.N. Azlan ◽

...

Keyword(s):

Grain Size ◽

Gallium Nitride ◽

Dopant Concentration ◽

Crystalline Quality ◽

Size Distributions ◽

Grain Size Distributions ◽

P Type

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Porous Silicon Morphology: Photo-Electrochemically Etched by Different Laser Wavelengths

Journal of Nanotechnology in Engineering and Medicine ◽

10.1115/1.4030768 ◽

2015 ◽

Vol 6 (1) ◽

Cited By ~ 1

Author(s):

Shereen M. Faraj ◽

Shaimaa M. Abd Al-Baqi ◽

Nasreen R. Jber ◽

Johnny Fisher

Keyword(s):

Porous Silicon ◽

Electrochemical Etching ◽

Diode Lasers ◽

Focus Of Attention ◽

Blue Laser ◽

Uniform Structure ◽

Porous Layers ◽

Current Densities ◽

P Type ◽

532 Nm

Porous silicon (PS) has become the focus of attention in upgrading silicon for optoelectronics. In this work, various structures were produced depending on the formation parameters by photo-electrochemical etching (PECE) process of n- and p-type silicon wafer at different time durations (5–90 mins) and different current densities (5, 15, and 20 mA/cm2) for each set of time durations. Diode lasers of 405 nm, 473 nm, and 532 nm wavelengths, each 50 mW power, were used to illuminate the surface of the samples during the etching process. The results showed that controlled porous layers were achieved by using blue laser, giving uniform structure which can make it possible to dispense with expensive methods of patterning the silicon.

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