Connaissance

1.2 Nitrure de gallium (GaN) - Définition

1.2Gallium Nitride(GaN)-Definition Despite the fact that GaN has been studied far more extensively than the other group III nitrides, further investigations are still needed to approach the level of understanding of technologically important materials such as Si and GaAs. GaN growth often suffers from large background n-type carrier concentrations because of native defects and, [...]

2018-07-12 En savoir plus ...

1.2.1 Chemical Properties of GaN

1.2.1 Chemical Properties of GaN Since Johnson et al. [139] first synthesized GaN in 1932, a large body of information has repeatedly indicated that GaN is an exceedingly stable compound exhibiting significant hardness. It is this chemical stability at elevated temperatures combined with its hardness that has made GaN an attractive material for [...]

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1.2.2 Mechanical Properties of GaN

1.2.2 Mechanical Properties of GaN GaNhas a molecular weight of 83.7267 g mol1 in the hexagonalwurtzite structure.The lattice constant of early samples of GaN showed a dependence on growth conditions, impurity concentration, and film stoichiometry [151]. These observations were attributed to a high concentration of interstitial and bulk extended defects. A case in point [...]

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1.2.3 Thermal Properties of GaN

1.2.3 Propriétés thermiques du GaN Dans une veine similaire, le GaN et d'autres semi-conducteurs de nitrure de groupe III alliés sont cultivés à des températures élevées et également soumis à des températures de jonction accrues pendant le fonctionnement d'appareils tels que des amplificateurs et des dispositifs électroluminescents. Ainsi, les structures sont également soumises à des variations thermiques. Dans ce contexte, il [...]

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1.1 Structure cristalline des nitrures

1.1 Structure cristalline des nitrures Les nitrures du groupe III peuvent être de structures cristallines: la wurtzite (Wz), la blende de zinc (ZB) et le sel gemme. Dans des conditions ambiantes, la structure thermodynamiquement stable est en wurtzite pour AlN, GaN et InN en vrac. La structure de la blende de zinc pour GaN et InN a été stabilisée par la croissance épitaxiale de films minces [...]

2018-07-10 En savoir plus ...

Propriétés générales des nitrures

Introduction GaN en tant que représentant de ses cousins ​​binaires, InN et AlN, et leurs ternaires avec le quaternaire, est considéré comme l'un des semi-conducteurs les plus importants après Si. Il n'est pas étonnant qu'il trouve de nombreuses applications dans l'éclairage et les affichages de toutes sortes, les lasers, les détecteurs et les amplificateurs haute puissance. Ces applications découlent [...]

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5-1 Introduction

5-1 Introduction Silicon carbide (SiC)-based semiconductor electronic devices and circuits are presently being developed for use in high-temperature, high-power, and high-radiation conditions under which conventional semiconductors cannot adequately perform. Silicon carbide’s ability to function under such extreme conditions is expected to enable significant improvements to a far-ranging variety of applications and systems. These range [...]

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5-2-1 SiC Material Properties

SILICON CARBIDE (SiC) materials are currently metamorphosing from research and development into a market driven manufacturing product. SiC substrates are currently used as the base for a large fraction of the world production of green, blue, and ultraviolet light-emitting diodes (LEDs). Emerging markets for SiC homoepitaxy include high-power switching [...]

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5-2-1-1 SiC Crystallography

5-2-1-1 SiC Crystallography Silicon carbide occurs in many different crystal structures, called polytypes. Despite the fact that all SiC polytypes chemically consist of 50% carbon atoms covalently bonded with 50% silicon atoms, each SiC polytype has its own distinct set of electrical semiconductor properties. While there are over 100 known [...]

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5-2-1-2 Electrical Properties

5-2-1-2 Electrical Properties Owing to the differing arrangement of Si and C atoms within the SiC crystal lattice, each SiC polytype exhibits unique fundamental electrical and optical properties. Some of the more important semiconductor electrical properties of the 3C, 4H, and 6H SiC polytypes are given in Table 5.1. Much more detailed electrical [...]

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