A Comparative Analysis of Effect of Temperature on Band-Gap Energy of Gallium Nitride and Its Stability Beyond Room Temperature Using Bose–einstein Model and Varshni’s Model

Abstract


 High temperature stability of band-gap energy of active layer material of a semiconductor device is one of the major challenges in the field of semiconductor optoelectronic device design. It is essential to ensure the stability in different band-gap energy dependent characteristics of the semiconductor material used to fabricate these devices either directly or indirectly. Different models have been widely used to analyze the band-gap energy dependent characteristics at different temperatures. The most commonly used methods to analyze the temperature dependence of band-gap energy of semiconductor materials are: Passler model, Bose–Einstein model and Varshni’s model. This paper is going to report the limitation of the Bose–Einstein model through a comparative analysis between Bose–Einstein model and Varshni’s model. The numerical analysis is carried out considering GaN as it is one of the most widely used semiconductor materials all over the world. From the numerical results it is ascertained that below the temperature of 95o K both the models show almost same characteristics. However beyond 95o K Varshni’s model shows weaker temperature dependence than that of Bose–Einstein model. Varshni’s model shows that the band-gap energy of GaN at 300o K is found to be 3.43eV, which establishes a good agreement with the theoretically calculated band-gap energy of GaN for operating at room temperature.

Band-edge absorption characteristics of semi-insulating indium phosphide under unified Franz-Keldysh and Einstein models

“…The deviations seen between the experimental and theoretical results could also potentially be attributed to the accuracy of the (simple) Einstein model in characterizing the band edge. With this in mind, we have repeated the fitting in this work with the (more common) Varshni model, as it often shows better agreement between experimental and theoretical results [13,16]. The Varshni model is a simple empirical relation that assumes an average phonon energy, and so it is best used with semiconductors exhibiting little phonon dispersion at temperatures above 100 K [17].…”

Gallium Arsenide and Gallium Nitride Semiconductors for Power and Optoelectronics Devices Applications

“…The optical and electrical properties of semiconductors are determined by their Bandgap energy, and understanding the effect of temperature on bandgap energy is important in optoelectronic devices such as lasers, solar cells and so on [8].…”

“…This create high carrier concentration at the interface forming a 2DEG channel. In addition, strong spontaneous polarization effect and piezoelectric polarization effect has been observed in GaN as compared with GaAs materials, resulting the higher piezoelectric coefficient of GaN over GaAs [8]. This makes GaN more suitable for Nano sensor and Nano generator.…”

Hybrid NRZ/RZ line coding scheme based hybrid FSO/FO dual channel communication systems

“…In communication systems, the input electrical signals which carry the information to be transmitted are first converted into optical signals by modulating the optical source output through one of two mechanisms; by varying the drive current of source or by varying the light intensity at the optical source output [1][2][3][4][5][6][7][8][9][10][11][12]. The optical fiber has low attenuation coefficient and large angle of light acceptance cone [13][14][15][16][17][18][19][20][21][22]. The optical signal is propagating via the optical fiber within optical wavelengths range through several ray paths [23][24][25][26][27][28][29][30].…”