http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Palash Das,Nripendra N. Halder,Rahul Kumar,Sanjay Kr. Jana,Sanjib Kabi,Boris Borisov,Amir Dabiran,Peter Chow,Dhrubes Biswas 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.6
This paper presents an approach of compositional grading of the barrier in AlGaN/GaN quantum well heterostructure to achieve high two dimensional electron gas (2DEG) carrier concentration and mobility for RF power amplifier applications. Plasma assisted Molecular Beam Epitaxy (PAMBE) has been used to grow compositionally graded AlGaN/GaN and AlGaN/AlN/GaN heterostructures. In-situ cathodoluminescence (CL) and ex-situ high resolution x-ray diffraction (HRXRD) along with high resolution transmission electron microscopy (HRTEM) techniques were used to study the compositions and thicknesses of grown heterostructures. Ohmic contact formation for all the samples were found to be challenging due to unusual surface behavior and thus addressed with three different metallization schemes. The graded AlGaN/GaN and AlGaN/AlN/GaN heterostructures show 2DEG carrier concentrations of 2.0 × 1013 cm–2 and 2.3 × 1013 cm–2 with carrier mobility of 764 cm2v–1s–1 and 960 cm2v–1s–1, respectively at room temperature. A performance index has been proposed to correlate the obtained results with its suitability for particular RF applications.
Palash Das,Sanjay Kumar Jana,Nripendra N. Halder,S. Mallik,S. S. Mahato,A. K. Panda,Peter P. Chow,Dhrubes Biswas 대한금속·재료학회 2018 ELECTRONIC MATERIALS LETTERS Vol.14 No.6
In this letter, a standard deviation based optimization technique has been applied on High Resolution X-ray Diff raction symmetricand asymmetric scan results to accurately determine the Aluminum molar fraction and lattice relaxation of MolecularBeam Epitaxy grown compositionally graded Aluminum Gallium Nitride (AlGaN)/Aluminum Nitride/Gallium Nitride(GaN) heterostructures. Mathews–Blakeslee critical thickness model has been applied in an alternative way to determinethe partially relaxed AlGaN epilayer thicknesses. The coupling coeffi cient determination has been presented in a diff erentperspective involving sample tilt method by off set between the asymmetric planes of GaN and AlGaN. Sample tilt is furtherincreased to determine mosaic tilt ranging between 0.01° and 0.1°.