A Chemical Perspective of GaN Polarity: The use of Hydrogen Plasma Dry Etching Versus NaOH Wet Etching to Determine Polarity

MRS Proceedings ◽

10.1557/proc-722-k3.4 ◽

2002 ◽

Vol 722 ◽

Cited By ~ 3

Author(s):

Maria Losurdo ◽

MariaMichela Giangregorio ◽

Pio Capezzuto ◽

Giovanni Bruno ◽

Gon Namkoong ◽

...

Keyword(s):

Surface Morphology ◽

Plasma Etching ◽

Hydrogen Plasma ◽

Dry Etching ◽

Surface Reactivity ◽

Wet Etching ◽

Hydrogen Treatment

AbstractThe use of dry hydrogen plasma etching is evaluated for determination of GaN polarity and critically compared to wet etching in NaOH. It is shown that hydrogen plasma etching is effective in revealing inversion domains (IDs) and some types of dislocations. This is because the surface morphology is unchanged by the hydrogen treatment, and, hence, the surface reactivity is not masked.

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Dry Etching Techniques and Chemistries for III-V Semiconductors

MRS Proceedings ◽

10.1557/proc-216-277 ◽

1990 ◽

Vol 216 ◽

Cited By ~ 4

Author(s):

S. J. Pearton

Keyword(s):

Plasma Etching ◽

Cyclotron Resonance ◽

Electron Cyclotron Resonance ◽

Surface Damage ◽

Dry Etching ◽

Near Surface ◽

Lattice Disorder ◽

Ecr Plasma ◽

Surface Morphologies

ABSTRACTDry etching of HI-V materials using both Cl-based (CCl2F2, SiCl4, BCl3, Cl2) and CH4/H2 discharges will be reviewed. The etch rates using chlorine-based mixtures are generally faster than those utilizing CH4/H2, but the latter gives smoother surface morphologies for In-containing compounds. The use of microwave (2.45 GHz) electron cyclotron resonance (ECR) discharges minimizes the depth of lattice disorder resulting from dry etching, relative to conventional RF (13.56 MHz) discharges. Recent results on the systematics of ECR plasma etching of both In- and Ga-based III-V semiconductors using CCl2F2/O2 and CH4/H2 mixtures will be discussed, including the determination of the maximum self-biases allowable which do not induce near-surface damage to the semiconductor. A further key issue is the prevention of changes in the surface stoichiometry of materials such as InP, where the lattice constituents may have considerably different volatilities in the particular discharge.

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Tailoring the surface morphology of carbon nanotube forests by plasma etching: a parametric study

Carbon ◽

10.1016/j.carbon.2021.04.066 ◽

2021 ◽

Author(s):

Seungju Seo ◽

Sanha Kim ◽

Shun Yamamoto ◽

Kehang Cui ◽

Takashi Kodama ◽

...

Keyword(s):

Carbon Nanotube ◽

Surface Morphology ◽

Plasma Etching ◽

Parametric Study ◽

Carbon Nanotube Forests

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The Effect of Catalyst on Carbon Nanotubes (CNTs) Synthesized by Catalytic Chemical Vapor Deposition (CVD) Technique

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.364.232 ◽

2011 ◽

Vol 364 ◽

pp. 232-237 ◽

Cited By ~ 4

Author(s):

S.Y. Lim ◽

M.M. Norani

Keyword(s):

Carbon Nanotubes ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Dry Etching ◽

Wet Etching ◽

Etching Time ◽

Catalytic Chemical Vapor Deposition ◽

Catalyst Pretreatment ◽

Diameter Range

Catalyst plays a crucial role in determining the characteristics of carbon nanotubes (CNTs) produced by using thermal catalytic chemical vapor deposition (CVD). It is essential to investigate how the catalyst preparation affects the characteristics of CNTs because certain application demands specific size for optimum performance. This study reports the effect of the types of catalyst and the duration of the catalyst pre-treatment (wet etching time, dry etching time and ball milling) on the diameter of CNTs. The synthesized CNTs samples were characterized by scanning and transmission electron microscopy and Raman spectroscopy. Wet etching (2M hydrofluoric acid) time was varied from 1 to 2.5 hrs and the diameter range was found to be in the range of 23 to 52 nm. The diameter range for CNTs produced for 3 hrs and 5 hrs of dry etching treatment (with ammonia gas) are 38 to 51 nm and 23 to 48 nm, respectively. The diameter size of CNTs produced using Ni (14 to 25 nm) was found to be smaller than Fe (38 to 51 nm). There is a significant decrease in the diameter of CNTs by prolonging the wet etching period. Shorter and curly shaped CNTs can also be obtained by using Ni as the catalyst. Keywords: chemical vapor deposition, carbon nanotubes, catalyst pretreatment

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Polarity determination of InN by wet etching

physica status solidi (a) ◽

10.1002/pssa.200461439 ◽

2005 ◽

Vol 202 (5) ◽

pp. 773-776 ◽

Cited By ~ 41

Author(s):

Daisuke Muto ◽

Tsutomu Araki ◽

Hiroyuki Naoi ◽

Fumie Matsuda ◽

Yasushi Nanishi

Keyword(s):

Wet Etching ◽

Polarity Determination

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Problems of Surface Morphology and Layer Deposition during Plasma Etching Processes (II) Si-etching in CF4-, CF4/O2-and CF4/H2 Plasmas

Crystal Research and Technology ◽

10.1002/crat.2170170706 ◽

1982 ◽

Vol 17 (7) ◽

pp. 821-825 ◽

Cited By ~ 5

Author(s):

H.-J. Tiller ◽

J. Krausse ◽

R. Voigt

Keyword(s):

Surface Morphology ◽

Plasma Etching ◽

Layer Deposition

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Surface Structure and Cells Adhesion on Doped Polyethylene

Materials Science Forum ◽

10.4028/www.scientific.net/msf.567-568.253 ◽

2007 ◽

Vol 567-568 ◽

pp. 253-256

Author(s):

Regina Mikulíková ◽

Kateřina Kolářová ◽

Václav Švorčík ◽

Barbora Dvořánková ◽

Tomáš Sopuch

Keyword(s):

Surface Morphology ◽

Ftir Spectroscopy ◽

Crystalline Phase ◽

Film Surface ◽

Surface Wettability ◽

Oxidized Cellulose ◽

3T3 Fibroblasts ◽

Doped Polymer

The properties of polyethylene doped with Ca2+ salt of oxidized cellulose was studied by different techniques. FTIR spectroscopy was used for the determination of crystalline phase in polymer film, surface wettability was determined by standard goniometry and surface morphology was examined by SEM microscopy. Adhesion of mouse 3T3 fibroblasts on the doped polymer was studied in vitro. It was found that the polyethylene doped with the cellulose derivative can be sterilized in boiling water. The number and homogeneity of adhering cells were shown to depend on the surface wettability and morphology.

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Hydrogen-plasma etching of ion beam deposited c-BN films: An in situ investigation of the surface with electron spectroscopy

Journal of Applied Physics ◽

10.1063/1.1320031 ◽

2000 ◽

Vol 88 (10) ◽

pp. 5597-5604 ◽

Cited By ~ 19

Author(s):

P. Reinke ◽

P. Oelhafen ◽

H. Feldermann ◽

C. Ronning ◽

H. Hofsäss

Keyword(s):

Plasma Etching ◽

Electron Spectroscopy ◽

Ion Beam ◽

Hydrogen Plasma ◽

In Situ Investigation

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Plasma Chemistries for Dry Etching GaN, AIN, InGaN and InAIN

MRS Proceedings ◽

10.1557/proc-421-309 ◽

1996 ◽

Vol 421 ◽

Author(s):

S. J. Pearton ◽

C. B. Vartuli ◽

J. W. Lee ◽

S. M. Donovan ◽

J. D. MacKenzie ◽

...

Keyword(s):

Hydrogen Plasma ◽

Critical Factor ◽

Dry Etching ◽

Ion Energies ◽

Volatile Products ◽

Etch Rates

AbstractEtch rates up to 7,000Å/min. for GaN are obtained in Cl2/H2/Ar or BCl3/Ar ECR discharges at 1–3mTorr and moderate dc biases. Typical rates with HI/H2 are about a factor of three lower under the same conditions, while CH4/H2 produces maximum rates of only ˜2000Å/min. The role of additives such as SF6, N2, H2 or Ar to the basic chlorine, bromine, iodine or methane-hydrogen plasma chemistries are discussed. Their effect can be either chemical ( in forming volatile products with N) or physical ( in breaking bonds or enhancing desorption of the etch products). The nitrides differ from conventional III-V's in that bondbreaking to allow formation of the etch products is a critical factor. Threshold ion energies for the onset of etching of GaN, InGaN and InAlN are ≥75eV.

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