Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 32451
Effects of Double Delta Doping on Millimeter and Sub-millimeter Wave Response of Two-Dimensional Hot Electrons in GaAs Nanostructures

Authors: N. Basanta Singh, Sanjoy Deb, G. P Mishra, Subir Kumar Sarkar


Carrier mobility has become the most important characteristic of high speed low dimensional devices. Due to development of very fast switching semiconductor devices, speed of computer and communication equipment has been increasing day by day and will continue to do so in future. As the response of any device depends on the carrier motion within the devices, extensive studies of carrier mobility in the devices has been established essential for the growth in the field of low dimensional devices. Small-signal ac transport of degenerate two-dimensional hot electrons in GaAs quantum wells is studied here incorporating deformation potential acoustic, polar optic and ionized impurity scattering in the framework of heated drifted Fermi-Dirac carrier distribution. Delta doping is considered in the calculations to investigate the effects of double delta doping on millimeter and submillimeter wave response of two dimensional hot electrons in GaAs nanostructures. The inclusion of delta doping is found to enhance considerably the two dimensional electron density which in turn improves the carrier mobility (both ac and dc) values in the GaAs quantum wells thereby providing scope of getting higher speed devices in future.

Keywords: Carrier mobility, Delta doping, Hot carriers, Quantum wells.

Digital Object Identifier (DOI):

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1569


[1] "Technology roadmap for nanoelectronics," Published by European Commission IST programme on Future and Emerging Technologies, Nov. 2000. Available:
[2] R. Dingle, H. L. Stormer, A. C. Gossard and W. Wiegmann, "Electron mobilities in modulation-doped semiconductor heterojunction superlattices," Appl. Phys. Lett., vol. 33, no. 7, pp. 665-667, Oct. 1978.
[3] J. J. Harris, J A Pals and R Woltjer, "Electronic transport in lowdimensional structures," Rep. Prog. Phys., vol. 52, pp.1217-1266, Oct. 1989.
[4] C T Foxon, J J Harris, D Hilton, J Hewett and C Roberts, "Optimisation of (Al,Ga)As/GaAs two-dimensional electron gas structures for low carrier densities & ultra high mobilities at low temperature, "Semicond. Sci. Technol., vol. 4, pp. 582-595, Apr. 1989.
[5] M. Heiblum, E. E. Mendez and F. Stern, "High mobility electron gas in selectively doped n:AlGaAs/GaAs heterojunctions," Appl. Phys. Lett., vol. 44, no.11, pp. 1064-1066, Jun. 1984
[6] E. F. Schubert, "Delta doping of III-V compound semiconductor: Fundamental and device applications, "J. Vac. Sci. Technol. A, vol. 87, no. 3, pp. 2980-2996, May 1990
[7] Guo-Qiang Hai, Nelson Studart and F. M. Peeters, "Electron mobility in two coupled layers, " Phys. Rev. B, vol. 52, no. 15, pp.11273-11276, Oct. 1995
[8] P. J. Price, "Two-dimensional electron transport in semiconductor layers. I. Phonon scattering," Ann. Phys., vol. 133, pp. 217-239, May. 1981.
[9] T. Tsuchiya and T Ando, "Electron-phonon interaction in GaAs/AlAs superlattices," Phys. Rev. B, vol. 47, no. 12, pp. 7240-7252, Mar. 1993.
[10] T. Tsuchiya and T Ando, "Mobility enhancement in quantum wells by electronic-state modulation," Phys. Rev. B, vol. 48, no. 7, pp. 4599-4603, Aug. 1993
[11] Subir Kumar Sarkar, "Effects of wave function modulation on highfrequency carrier transport in quantum wells under high biasing field," Indian J. Phys., vol. 78, no. 7, pp. 535-538, 2004.
[12] X. T Zhu, H. Goronkin, G. N. Maracas, R. Droopad and M. Stroscio, " Electron mobility enhancement by confining optical phonons in GaAs/AlAs multiple quantum wells," Appl. Phys. Lett., vol. 60, no. 17, pp. 2141-2143, Apr. 1992.
[13] J. Pozela, V. Juciene , A. Namajunas and K. Pozela, "Electron mobility and subband population tuning by a phonon wall inserted in a semiconductor quantum well, "J. Appl. Phys., vol. 81, no. 4, pp. 1775- 1780, Feb. 1997.
[14] H. Harikawa, H. Sakaki and J. Yoshino, "Concentrations of electrons in selectively doped GaAlAs/GaAs heterojunction and its dependence on spacer layer thickness and gate electric field," Appl. Phys. Lett., vol. 45, no. 3, pp. 253-255, Aug. 1984.
[15] L. Chico, W Laskolski, R Perez-Alvarez and F Garcia Moliner, "On the theory of GaAs-based quantum wells with external -doping, J. Phys.: Condens. Matters, vol. 5, pp.9069-9076 Aug. 1993.
[16] H.J Gossmann and E.F. Schubert, "Delta doping in Silicone," Solid State and Material Sc., vol. 18, no. 1, pp. 1-67, Jan. 1993
[17] Ikai Lo, Y. C. Chang, H. M. Weng, and J. C. Chiang, "Two-dimensional electron gas in -doped double quantum wells for photodetector application," J. Appl. Phys., vol. 81, no. 12, pp. 8112-8114, Jun. 1997.
[18] E. F Schubert, J. E. Cunningham, W.T Tsang and G.L. Timp, "Selectively -doped AlxGa1-xAs/GaAs heterostructures with high twodimensional electron-gas concentrations n2DEG>1.5x1012 cm-2 for fieldeffect transistors, "Appl. Phys. Lett., vol. 51, no. 15, pp. 1170-1172 Oct. 1987
[19] E. F Schubert, A. Fischer and K. Ploog, "The delta doped field effect transistor (FET), "IEEE Trans. Electron Devices, vol. 33, no. 5, pp. 625-632 May 1986.
[20] E. F Schubert, J. E. Cunningham, W.T Tsang, "Electron-mobility enhancement and electron-concentration enhancement in -doped n- GaAs at T=300K, " Solid State Commun., vol. 63, pp. 591-594, 1987
[21] E. F Schubert, J. E. Cunningham, and W.T Tsang, "Self-aligned enhancement-mode and depletion-mode GaAs field effect transistor employing the -doping technique," Appl. Phys. Lett., 49, no. 25, pp. 1729-1731, Dec. 1986.
[22] E. F Schubert, A. Fischer, Y. Horikoshi, and K. Ploog, "GaAs sawtooth superlattice laser emitting at wavelength λ>0.9┬Ám," Appl. Phys. Lett., vol. 47, no. 3, pp. 219-221, Aug. 1985.
[23] H.J Gossmann and E.F. Schubert, "Delta doping in Silicone," Solid State & Material Sc., vol. 18, no. 1, pp. 1-67, Jan. 1993.
[24] J. E. Cunningham, W.T. Tsang, G. Timp, E. F. Schubert, A. M. Chang and K. Owusu-Sekyer, " Quantum size effects in monolayer doped heterostructures," Phys. Rev. B, vol. 37,no. 8, pp. 4317-4320, Mar. 1988.
[25] T. Y Kuo, J. E Cunningham, E. F Schubert, W. T Tsang, T. H Chiu, R Ren and C. G Fonstad, " Selectively -doped quantum well transistor grown by gas source molecular beam epitaxy," J. Appl. Phys., vol. 64, no. 6, pp. 3324- 3327, Sept. 1988.
[26] V.M.S.Gomes,A.S. Chavas, J. R Leite and J.M.Worlock,"Self-consistent calculations of the two-dimensional electron density in modulationdoped superlattices," Phys. Rev. B, 35 (8), pp. 3984-3989, Mar. 1978.
[27] S. K. Sarkar,P. K. Ghosh and D. Chattopadhyay, "Calculations of highfrequency response of two-dimensional hot electrons in GaAs quantum wells," J. Appl. Phys., vol. 78, no. 1, pp. 283-287, July 1995.
[28] S. K. Sarkar, "Multiple level optimization for high frequency ac mobility in GaAs quantum wells under hot-electron condition," Comp. Mat. Sci., vol-29, pp. 243-249, 2004.
[29] S. K. Sarkar, A. Moi , C. Puttamadappa , A.K. Day and M.K. Naskar, "Application of genetic algorithm to determine the optimized system parameters of GaAs quantum wells for better high-frequency performance under hot electron condition," Physica B, vol. 325, pp.189- 194, 2003.
[30] J. P. Leburton, "Size effects on polar optical phonon scattering of 1-D and 2-D electron gas in synthetic