Admittance spectroscopy of GaAs/InGaP MQW structures

✍ Scribed by E. Gombia; C. Ghezzi; A. Parisini; L. Tarricone; M. Longo

• Book ID: 103843787
• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 236 KB
• Volume: 147
• Category: Article
• ISSN: 0921-5107
• DOI: 10.1016/j.mseb.2007.08.017

✦ Synopsis

An accurate determination of the valence band discontinuity of the lattice matched GaAs/InGaP heterostructure is performed by admittance spectroscopy measurements in p + /MQW/n + structures grown by metal-organic vapour phase epitaxy (MOVPE) using tertiarybutylarsine and tertiarybutylphosphine as alternative precursors for the V group elements. Through the analysis of the temperature dependence of the resonance frequency at which the isothermal curves of the conductance over frequency G(ω)/ω have the maximum, the energy separation of 336 ± 5 meV between the lowest heavy hole quantum level in the GaAs wells and the InGaP valence band top is obtained. A valence band discontinuity of E V = 346 ± 5 meV is then derived by accounting for the calculated confinement energy of heavy holes (E hh 1 = 10 meV). Experimental values of E V previously reported in the literature spread over the wide range of 300-400 meV.