Temperature-dependent charge-carrier transport between Si-δ-doped layers and AlGaAs/InGaAs/AlGaAs quantum well with various space layer thicknesses measured by Hall-effect analysis

• Published in: Scientific reports 2020-07, Vol.10 (1), p.12503-12503, Article 12503
• Main Authors: Su, Wilson Yeung-Sy, Lu, Victor Chien-Pin, Wu, Chii-Bin, Wang, Jyh-Shyang, Shen, Ji-Lin, Chiu, Kuan-Cheng
• Format: Article
• Language: English
• Subjects: 639/766/1130; 639/766/119; 639/925/927; Humanities and Social Sciences; Hysteresis; multidisciplinary; Organic chemicals; Science; Science (multidisciplinary); Sensors; Standard deviation
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-69153-1

Temperature ( T  = 40 ~ 300 K) dependence of Hall-effect analysis on the dual Si-δ-doped AlGaAs/InGaAs/AlGaAs quantum-well (QW) structures with various space layer thicknesses ( t S  = 5, 10 and 15 nm) was performed. An interesting hysteresis behavior of electron sheet concentration [ n 2D ( T )] was observed for t S  = 10 and 15 nm but not for t S  = 5 nm. A model involving two different activation barriers encountered respectively by electrons in the active QW and by electrons in the δ-doped layers is proposed to account for the hysteresis behavior. However, for small enough t S (= 5 nm ≤ 2.5  s , where s  = 2.0 nm is the standard deviation of the Gaussian fit to the Si-δ-doped profile), the distribution of Si dopants near active QW acted as a specific form of “modulation doping” and can not be regarded as an ideal δ-doping. These Si dopants nearby the active QW effectively increase the magnitude of n 2D , and hence no hysteresis curve was observed. Finally, effects from t S on the T -dependence of electron mobility in active QW channel are also discussed.