Strain relaxation in lattice-mismatched epitaxy

To date, primarily only idealized equilibrium models for the growth mode and strain relaxation of elastically strained overlayers have been proposed. Here we present a general continuum model for lattice-mismatched epitaxy. As molecular beam epitaxy is inherently a nonequilibrium growth process, surface diffusion kinetics is incorporated in the model. Additionally, a new strain relaxation mechanism in a dislocation-free film is considered. Experimental support for our view is obtained from measurements made by reflection high energy electron diffraction, scanning tunneling microscopy, and transmission electron microscopy on the growth of InGaAs on GaAs(100). These results demonstrate the strong effects which strain, surface diffusion kinetics, and surface energy have on growth mode. From analytical and numerical analysis in 1 + 1 dimensions, the interrelationship of such physical factors is revealed. Our improved understanding enables control over the growth behavior of strained-layer superlattices and heterostructures.

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Activation barriers to strain relaxation in lattice-mismatched epitaxy

Physical Review B ◽

10.1103/physrevb.40.1681 ◽

1989 ◽

Vol 40 (3) ◽

pp. 1681-1684 ◽

Cited By ~ 72

Author(s):

R. Hull ◽

J. C. Bean ◽

D. J. Werder ◽

R. E. Leibenguth

Keyword(s):

Strain Relaxation ◽

Activation Barriers ◽

Lattice Mismatched Epitaxy

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Strain Relaxation Mechanisms in Lattice Mismatched Epitaxy

MRS Proceedings ◽

10.1557/proc-198-459 ◽

1990 ◽

Vol 198 ◽

Cited By ~ 2

Author(s):

R. Hull ◽

J.C. Bean ◽

J.M. Bonar ◽

L. Peticolas

Keyword(s):

Strain Relaxation ◽

Epitaxial Layers ◽

Misfit Dislocations ◽

Strained Layer ◽

Device Structures ◽

Lattice Mismatched Epitaxy

ABSTRACTThe relaxation of strained epitaxial layers by the introduction of misfit dislocations is reviewed. Current theoretical and experimental understanding of the nucleation, propagation and interaction of misfit dislocations are summarized. The ramifications for applicability of strained layer epitaxy to practical device structures are discussed.

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New approach to the strain relaxation mechanism in lattice-mismatched epitaxy

Thin Solid Films ◽

10.1016/0040-6090(91)90154-p ◽

1991 ◽

Vol 201 (1) ◽

pp. 59-67 ◽

Cited By ~ 10

Author(s):

H. Tatsuoka ◽

H. Kuwabara ◽

Y. Nakanishi ◽

H. Fujiyasu

Keyword(s):

Strain Relaxation ◽

Relaxation Mechanism ◽

New Approach ◽

Lattice Mismatched Epitaxy

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Exploiting long-range atomic ordering for the investigation of strain relaxation in lattice-mismatched epitaxy

Applied Surface Science ◽

10.1016/s0169-4332(01)00731-0 ◽

2002 ◽

Vol 188 (1-2) ◽

pp. 61-68 ◽

Cited By ~ 11

Author(s):

E. Spiecker ◽

M. Seibt ◽

W. Schröter ◽

R. Winterhoff ◽

F. Scholz

Keyword(s):

Long Range ◽

Strain Relaxation ◽

Atomic Ordering ◽

Lattice Mismatched Epitaxy

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TEM study of phosphorus-implanted pseudomorphic Si0.88Ge0.12 on Si(100)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138713 ◽

1995 ◽

Vol 53 ◽

pp. 468-469

Author(s):

N. David Theodore ◽

Donald Y.C Lie ◽

J. H. Song ◽

Peter Crozier

Keyword(s):

Integrated Circuits ◽

Heterojunction Bipolar Transistors ◽

Integrated Circuit ◽

High Speed ◽

Room Temperature ◽

Strain Relaxation ◽

Bipolar Transistors ◽

Sige Hbt ◽

Integrated Circuit Manufacturing ◽

Microstructural Behavior

SiGe is being extensively investigated for use in heterojunction bipolar-transistors (HBT) and high-speed integrated circuits. The material offers adjustable bandgaps, improved carrier mobilities over Si homostructures, and compatibility with Si-based integrated-circuit manufacturing. SiGe HBT performance can be improved by increasing the base-doping or by widening the base link-region by ion implantation. A problem that arises however is that implantation can enhance strain-relaxation of SiGe/Si.Furthermore, once misfit or threading dislocations result, the defects can give rise to recombination-generation in depletion regions of semiconductor devices. It is of relevance therefore to study the damage and anneal behavior of implanted SiGe layers. The present study investigates the microstructural behavior of phosphorus implanted pseudomorphic metastable Si0.88Ge0.12 films on silicon, exposed to various anneals.Metastable pseudomorphic Si0.88Ge0.12 films were grown ~265 nm thick on a silicon wafer by molecular-beam epitaxy. Pieces of this wafer were then implanted at room temperature with 100 keV phosphorus ions to a dose of 1.5×1015 cm-2.

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Strain Relaxation and In-Situ Observation of Voiding in Passivated Aluminum Alloy Lines.

MRS Proceedings ◽

10.1557/proc-308-249 ◽

1993 ◽

Vol 308 ◽

Cited By ~ 3

Author(s):

Paul R. Besser ◽

Thomas N. Marieb ◽

John C. Bravman

Keyword(s):

Strain Relaxation ◽

Grazing Incidence ◽

Scanning Transmission Electron Microscope ◽

In Situ Observation ◽

X Ray ◽

Scanning Transmission ◽

Length Width ◽

Measured Strain ◽

Ray Geometry

ABSTRACTStrain relaxation in passivated Al-0.5% Cu lines was measured using X-ray diffraction coupled with in-situ observation of the formation and growth of stress induced voids. Samples of 1 μm thick Al-0.5% Cu lines passivated with Si3N4 were heated to 380ºC, then cooled and held at 150ºC. During the test, principal strains along the length, width, and height of the line were determined using a grazing incidence x-ray geometry. From these measurements the hydrostatic strain in the metal was calculated and strain relaxation was observed. The thermal cycle was duplicated in a high voltage scanning transmission electron microscope equipped with a backscattered electron detector. The 1.25 μm wide lines were seen to have initial stress voids. Upon heating these voids reduced in size until no longer observable. Once the samples were cooled to 150ºC, voids reappeared and grew. The measured strain relaxation is discussed in terms of void and θ-phase (Al2Cu) formation.

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