RHEED Studies of Strained Layer Molecular Beam Epitaxy and Self Assembled Quantum Dots, Paul R. Berger

Student: Paul R. Berger (Ph.D 1990)

Advisor: Pallab K. Bhattacharya (University of Michigan, Ann Arbor)

Importance of the Problem:

Epitaxial growth prefers that the epilayer be lattice matched to the substrate, or underlayer, to avoid the formation of misfit dislocations created when a lattice mismatched layer exceeds its critical thickness and it becomes energetically favorable to create misfit dislocations. How the surface changes during strained growth was not well known in the late 1980's, when in situ surface studies using reflection high energy electron diffraction (RHEED) provided a pathway to investigate the surface during strained MBE growth.

Brief Description of Our Work and Results:

Developed an understanding of self-assembled quantum dot formation by the study of reflection high energy electron diffraction (RHEED) oscillations. From the RHEED studies, surface kinetics were examined for various alloys compositions and related to the constituents bond strengths. Expanded the understanding of lattice mismatched strained layer systems by developing a model of the MBE growth nucleation of the InGaAs on GaAs system. Showed for the first time how strain modifies the growth kinetics and thermodynamics which governs the strained growth modes. Proved a favorability toward 3-D island growth under normal growth conditions when the misfit exceeds about 2% which enable self-assembled quantum dot formation. Also measured the shift in surface lattice constant during strained layer epitaxy and illustrated metastable growth at reduced substrate temperatures.

Awards, Citations and Recognitions

Publications

Strained Layer Epitaxial Growth and Self-Assembled Quantum Dot Formation

  1. "Realization of In-Situ Sub Two-Dimensional Quantum Structures by Strained Layer Growth Phenomena in the InxGa1-xAs/GaAs System," J. Pamulapati, P. K. Bhattacharya, J. Singh, P. R. Berger, C. W. Snyder, B. G. Orr, and R. L. Tober, Journal of Electronic Materials, 25, pp. 479-483 (March 1996). PDF (1.25 MB)

  2. "Growth Phenomena and Characteristics of Strained InxGa1-xAs on GaAs," J. Pamulapati, P. Berger, K. Chang, J. Oh, Yi Chen, J. Singh, and P. Bhattacharya, Journal of Crystal Growth, 95, pp. 193-196 (1989).

  3. "Role of Strain and Growth Conditions on the Growth Front Profile of InxGa1-xAs on GaAs During the Pseudomorphic Growth Regime," Paul R. Berger, Kevin Chang, Pallab Bhattacharya, Jasprit Singh and K. K. Bajaj, Applied Physics Letters, 53, pp. 684-686 (August 22, 1988). PDF (572 kB) [Cited 206 times]

  4. "A Study of Strain Related Effects in the MBE Growth of InxGa1-xAs on GaAs Using RHEED," Paul R. Berger, Kevin Chang, Pallab K. Bhattacharya, and Jasprit Singh, Journal of Vacuum Science and Technology B, 5, pp. 1162-1166 (July/August 1987). PDF (536 kB) [Cited 38 times]

  5. "Molecular Beam Epitaxial Growth and Luminescence of InxGa1-xAs/InxAl1-xAs Multiquantum Wells On GaAs," Kevin Chang, Paul R. Berger, Jasprit Singh, and Pallab K. Bhattacharya, Applied Physics Letters, 51, pp. 261-263 (July 27, 1987). PDF (395 kB)

  6. "A Comparative Study of the Growth processes of GaAs, AlGaAs, InGaAs and InAlAs Lattice Matched and Non-lattice Matched Semiconductors Using High Energy Electron Diffraction," Paul R. Berger, Pallab K. Bhattacharya, and Jasprit Singh, Journal of Applied Physics, 61, pp. 2856-2860 (April 15, 1987). PDF (789 kB) [Cited 31 times]

  7. "Growth and Properties of In0.52Al0.48As/ In0.53Ga0.47As GaAs:In and InGaAs/GaAs Multilayers," F-Y. Juang, W-P. Hong, P. R. Berger, P. K. Bhattacharya, U. Das, and J. Singh, Journal of Crystal Growth, 81, pp. 373-377 (1987).

  8. "Low Defect Densities in Molecular Beam Epitaxial GaAs Achieved by Isoelectronic In Doping," Pallab K. Bhattacharya, Sunada Dhar, Paul Berger, and Feng-Yuh Juang, Applied Physics Letters, 49, pp. 470-472 (August 25, 1986). PDF (279 kB)

Impact of Strained Layer Epitaxy Upon Device Performance

  1. "The Relation of the Performance Characteristics of Pseudomorphic In0.53+xGa0.47-xAs/ In0.52Al0.48As (0 < x < 0.32) Modulation Doped Field Effect Transistors to Molecular Beam Epitaxial Growth Modes," J. Pamulapati, R. Lai, G. I. Ng, Y. C. Chen, P. R. Berger, P. K. Bhattacharya, J. Singh, and D. Pavlidis, Journal of Applied Physics, 68, pp. 347-350 (July 1, 1990). PDF (777 kB)

Conference Presentations

  1. "Growth Modes of (100) InxGa1-xAs Growth on GaAs Below Critical Thickness - Consequences for Pseudomorhic MODFET's," P. R. Berger, Y. C. Chen, Jasprit Singh, and P. Bhattacharya, 16th GaAs and Related Compounds Conference in Karuizawa, Japan (1989).

  2. "Growth Phenomena and Characteristics of Strained InxGa1-xAs on GaAs," J. Pamulapati, P. Berger, K. Chang, J. Oh, Y. Chen, J. Singh, P. Bhattacharya, and R. Gibala, 5th International Conference on Molecular Beam Epitaxy in Sapporo, Japan (1988).

  3. "In-Situ RHEED Studies to Understand the Dislocation Formation Process in Growth of InGaAs on GaAs," Paul R. Berger, Kevin Chang, Pallab K. Bhattacharya, Jasprit Singh, and K. K. Bajaj, Advances in Semiconductors and Superconductors: Physics and Device Applications in Newport Beach, CA (1988).

  4. "Dislocation Studies of Molecular Beam Hetero-Epitaxial Growth of Strained InGaAs on GaAs," Kevin Chang, John Mansfield, Ron Gibala, Paul R. Berger, Pallab K. Bhattacharya, and Jasprit Singh, TMS/AIME Annual Meeting in Phoenix, AZ (1988).

  5. "Molecular Beam Hetero-epitaxial Growth of InxGa1-xAs/InxAl1-xAs Multiquantum Wells on GaAs with In-situ RHEED Studies," Kevin Chang, Paul R. Berger, Pallab K. Bhattacharya, Jasprit Singh, D. Van Aiken, and R. Gibala, 29th Electronic Materials Conference in Santa Barbara, CA (1987).

  6. "TEM and RHEED Studies on MBE Growth of Strained InGaAs/GaAs," Kevin Chang, Paul R. Berger, Pallab K. Bhattacharya, Jasprit Singh, D. Van Aiken, and R. Gibala, American Physical Society Meeting in New York, NY (1987).

  7. "A Study of Strain Related Effects in the MBE Growth of InxGa1-xAs on GaAs Using RHEED," Paul R. Berger, Kevin Chang, Pallab K. Bhattacharya, and Jasprit Singh, 14th Physics and Chemistry of Semiconductor Interfaces Conference in Salt Lake City, Utah (1987).

  8. "Growth and Properties of In0.52Al0.48As/In0.53Ga0.47As, GaAs: In and InGaAs/GaAs Multilayers," F-Y. Juang, W-P. Hong, P. R. Berger, P. K. Bhattacharya, U. Das, and J. Singh, 4th International Conference on Molecular Beam Epitaxy in York, England (1986).

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Last updated December 28, 2009.


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