WO2006031257A2 - METHOD FOR GROWING Si-Ge SEMICONDUCTOR MATERIALS AND DEVICES ON SUBSTRATES - Google Patents
METHOD FOR GROWING Si-Ge SEMICONDUCTOR MATERIALS AND DEVICES ON SUBSTRATES Download PDFInfo
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Definitions
- Patent Application No. 60/610,120 filed on September 14, 2004, entitled "Synthesis of new compositions of matter in the (H 3 Ge) 4-x SiH x (x 0-3) family of Si-Ge hydrides: Novel pathways to Ge-rich Gei -x Si x heterostructures and nanostructures on Si" and naming as inventors John Kouvetakis, Ignatius S. T. Tsong, Jose Menendez, John Tolle, Cole J. Ritter III and Chang Wu Hu, the disclosure of which is incorporated herein by this reference.
- This invention relates generally to semiconductor materials. More particularly, it relates to a method for growing epitaxial Ge-rich SiGe layers on Si substrates using single source (H 3 Ge) x SiH 4-x precursor compounds incorporating SiGe, SiGe 2 , SiGe 3 and SiGe 4 building blocks.
- MBE molecular beam epitaxy
- UHV-CVD ultrahigh vacuum chemical vapor deposition
- gas-source MBE utilizing common hydrides such as silane (SiH 4 ) and germane (GeH 4 ) or disilane (Si 2 H 6 ) and digermane (Ge 2 H 6 ).
- the first is the formation of strained, defect-free Sii -x Ge x films, which may take the form of strained layer superlattices, as described by J. C. Bean, L. C. Feldman, A. T. Fiory, S. Nakahara and I. K. Robinson, "Ge x Sii- x /Si strained-layer superlattice grown by molecular- beam epitaxy", J. Vac. Sci. Technol. A, vol. 2, No. 2, 1984, pp. 436-440.
- the second is the growth of coherent islands and quantum dots.
- Sii -x Ge x alloys across the entire compositional range is highly desirable to achieve comprehensive band gap and strain engineering in the Si-Ge system.
- Materials with Ge rich concentrations are particularly desirable for the development of virtual substrates and buffer layers on Si for numerous device applications based on strained group TV materials and for integration of III-V and II-VI optical semiconductors with Si electronics.
- Si 1- ⁇ Ge* layers with strain-free microstructure and variable compositions and lattice constants are currently used in industrial processes as virtual substrates for growth of high mobility electronic devices based on strained Si and Ge films (channels). See M. T. Currie, S. B. Samavedam, T. A. Langdo, C. W. Leitz, and E. A.
- CMOS complementary metal on oxide semiconductor
- CMOS devices are subsequently built on top of the strained Si channel using conventional CMOS processing.
- the Si 1 - ⁇ Ge* buffer layers and virtual substrates need to fulfill a number of materials requirements such as low dislocation densities, low surface roughness as well as uniformity of strain, Ge content, and layer thickness. Low surface roughness and reduced threading defect densities are particularly important to ensure a uniform spatial stress distribution in the Si and Ge overlayer channels, and to prevent interface scattering which can compromise the strained-enhanced carrier mobility.
- Si 1 - X Ge x buffer layers on Si are based on growth of thick compositionally graded films in which the Si and Ge content in the buffer layer is varied up to 100 % Ge.
- the misfit strain between the Si 1-x Ge x epilayer and Si substrate is gradually relieved with increasing film thickness, as described by Y. J. Mii, Y. H. Xie, E. A. Fitzgerald, D. Monrow, F. A. Thiel, B. E. Weir, and L. C. Feldman, "Extremely high electron-mobility in Si/Ge x Si 1-x structures grown by molecular-beam epitaxy", Appl. Phys. Lett. vol. 59, No. 13, Sep 1991, pp. 1611- 1613; P.
- Currie, et al. for a 50% Ge concentration a layer thickness of 5-10 ⁇ m is required to achieve material having dislocation densities of 6 ⁇ 10 cm “2 and surface roughness with RMS values of ⁇ 30 nm.
- the defect densities and film roughness become much worse due to the increase in the lattice mismatch.
- This requires an even greater film thickness to achieve acceptable defect densities and a chemical-mechanical polishing (CMP) step to smoothen the surface before growing additional device structures.
- CMP chemical-mechanical polishing
- the method includes introducing near the surface of the substrate the gaseous precursor comprising (H 3 Ge) x SiH 4 .
- the gaseous precursor can be introduced in pure form or intermixed with an inert carrier gas. Suitable inert carrier gases include H 2 and N 2 .
- the gaseous precursor can be deposited by low pressure CVD, UHV- CVD or gas source MBE and can be introduced at relatively low temperature in a range, from about 25O 0 C to about 700 0 C, and at a pressure in a range from about 1 x 10 "7 Torr to at least about 5 Torr.
- the gaseous precursor can be introduced as a single gas source or as a mixture comprising (H 3 Ge) x SiH 4-x and a germanium hydride, a silicon hydride or a silicon hydride- halide.
- the method can be used to deposit on a substrate a layer comprising an epitaxial Si-Ge material formed as a strained or strain free layer having a planar surface or as coherent islands or quantum dots.
- the substrate can be a silicon substrate, such as Si(IOO).
- the SiGe x layer can be formed as a strained or strain free layer having a planar surface or it can be formed as quantum dots or coherent islands.
- the SiGe x layer can have an atomically planar surface morphology, a thickness less than one micron and a threading defect density of less than 10 5 /cm 2 .
- the Si-Ge layer can be doped with an element selected from the group consisting of boron, arsenic, phosphorus, antimony and an indium.
- the silicon substrate can be patterned to form a template for selective growth of semiconductors.
- the method of our invention provides a new low-temperature growth process leading to Ge-rich films with low defect concentrations and smooth surfaces.
- the mobility of Ge on the growth surface is much lower, thereby preventing mass segregation which in turn can lead to compositional and strain variations in the film.
- the mass segregation of dopants is negligible at low temperatures, which is particularly beneficial for development of devices that require layers with low thickness.
- the deposited Si-Ge materials possess the required morphological and microstructural characteristics for applications in high frequency electronic and optical systems, as well as templates and buffer layers for development of commercial devices based on high mobility Si and Ge channels. They can circumvent the need for previously-known compositionally graded Si x Ge 1-x buffer layers and lift off technologies by providing suitable SiGe layers having a uniform composition throughout the layer.
- FIG. 2 is set of micrographs of a layer with a stoichiometric SiGe composition grown on Si(IOO) according to the present invention, including: (top) a bright field cross-sectional transmission electron microscopy (XTEM) micrograph of the entire layer thickness; (bottom left) a micrograph of the interface region showing perfect epitaxial alignment between Si(IOO) and SiGe; and (bottom right) a micrograph showing SiGe growth on a step at the interface in which an edge dislocation that is parallel to the interface plane is visible in the vicinity of the step.
- XTEM transmission electron microscopy
- FIG. 3 is a set of low-energy electron microscopy (LEEM) images showing layer-by-layer growth of SiGe 2 on Si(IOO) according to the invention, including images showing: (a) the morphology of a clean surface; (b) deposition of the first layer; (c) the second layer; and (d) the third layer.
- LEEM low-energy electron microscopy
- FIG. 4 is a graph showing the temperature dependence of the first layer growth rates for SiH 3 GeH 3 , SiH 2 (GeH 3 ) 2 , SiH(GeH 3 ) 3 and Si(GeH 3 ) 4 precursors according to the invention, as well as for GeH 3 GeH 3 for comparison.
- FIG. 5 is an XTEM micrograph of a SiGe 2 layer grown on Si(IOO) according to the invention, showing that threading dislocations are concentrated at the interface region and do not propagate to the film surface, and that the layer is highly uniform in thickness and displays an atomically smooth and continuous surface morphology.
- FIG. 6 shows Rutherford backscattering (RBS) random (upper trace) and aligned (lower trace) spectra of a 200 lira SiGe 2 film grown on Si(IOO) according to the invention.
- FIG. 7 shows Raman spectra of SiGe 2 (bottom) and SiGe 3 (top) showing the characteristic Ge-Ge, Si-Ge and Si-Si peaks indicating fully relaxed materials.
- the SiGe 2 spectrum (bottom) also includes an additional sharp peak corresponding to the Si substrate
- FIG. 8 is a bright field XTEM image of a strain-free and atomically smooth SiGe 3 layer grown on Si(IOO) according to the invention, with an inset atomic resolution Z-contrast image of the interface region showing a well defined, abrupt and perfectly epitaxial interface microstructure.
- FIG. 9 shows RBS random (upper trace) and aligned (lower trace) spectra of a SiGe 3 (001) layer grown at 38O 0 C according to the invention.
- FIG. 10 is a XTEM image showing the atomically flat top surface of a
- SiGe 4 film according to the invention is SiGe 4 film according to the invention.
- FIG. 11 shows RBS random (upper trace) and aligned (lower trace) spectra of a SiGe 4 (001) layer according to the invention with a thickness of 0.5 ⁇ m.
- FIG. 12 is a set of micrographs showing SiGe 3 quantum dots grown on
- Si(IOO) including: (top) a bright field XTEM micrograph showing the highly coherent (no threading defects) SiGe 3 quantum dots of uniform size; (bottom left) a high-resolution Z-contrast image of the interface region showing perfect epitaxial alignment as well as a sharp and uniform interface; and (bottom right) an AFM image showing an ensemble of dome-shaped islands with a narrow size distribution and including an inset enlarged view showing the faceted islands.
- PCT/US04/43854 Their high volatility and facile reactivity make them particularly useful as precursors in low temperature (300 - 45O 0 C) film growth.
- a notable result is the precise control of the composition at the atomic level via incorporation of the entire Si/Ge framework of the precursor into the film at unprecedented low growth temperatures (300°C-450°C).
- Targeted deposition experiments of the precursor compounds have been conducted in the temperature range of about 300-700 0 C to delineate the parameter space for growth of device quality films and quantum dots directly on silicon substrates.
- the films are obtained in the low temperature range and fulfill crucial requirements as suitable candidates for development of lattice engineered "virtual substrates" on Si.
- Potential applications include integration of strained Si and Ge channel devices on silicon exhibiting extremely high electron and hole mobilities.
- depositions of the precursors yield assemblies of three-dimensional coherently strained islands (quantum dots) reflecting the stoichiometry of the precursor in all cases without any segregation of either Ge or Si
- the material morphology in our films can be controlled by the adjustment of a single parameter, i.e. the growth temperature at a given flux rate of the unimolecular source.
- a single parameter i.e. the growth temperature at a given flux rate of the unimolecular source.
- depositions of the precursors at 300 0 C - 45O 0 C produce exclusively relaxed layers with planar surfaces.
- FIGs. 2, 5, 8 and 10 show exemplary films of SiGe (partially relaxed), SiGe 2 , SiGe 3 and SiGe 4 , respectively, grown according to the invention.
- the layers obtained using the method of our invention at deposition temperatures in a range of 300 0 C - 45O 0 C are of much higher quality than those with comparable thickness and compositions previously obtained using conventional sources under similar conditions.
- Our films display low threading defect densities with the bulk of the defects concentrated at the Si interface. They grow strain free and highly planar, circumventing entirely the need for graded compositions or lift-off technologies and post-growth chemical mechanical polishing to smoothen their surface. Highlights of the successful fabrication of these films include: (i) unprecedented low temperature synthesis (300°C-450°C), (ii) atomically smooth and defect-free surface morphology (mismatch induced defects are primarily concentrated at the interface), (iii) strain-free microstructure, and (iv) excellent thermal stability of layer planarity. These materials therefore fulfill the crucial requirements as suitable candidates for development of lattice engineered "virtual substrates" with lattice parameters in the 5.5 A to 5.65 A range.
- FIG. 12 shows an exemplary set of SiGe 3 quantum dots grown according to the invention at 600 0 C. Growth of SiGe x Layers on Silicon
- CVD chamber equipped with a low-energy electron microscope (LEEM) for in situ real time observation of the growth process.
- the base pressure of the chamber was 2 x 10 "10 Torr.
- Film growth was obtained by exposing the substrate surface to the gaseous precursor admitted via a leak valve. Partial pressures in the W '7 and IO '6 Torr range were used for deposition.
- the flux of the precursor was delivered via a glass inlet tube, which passed through the apertures in the objective lens of the LEEM.
- the inlet tube was positioned at 2.5 cm from the substrate at an angle of 16° to its surface.
- the substrates were p-type Si(IOO) (p -50 ⁇ cm) and were prepared for epitaxy by repeated flashing at 1240°C to vaporize the native oxide layer from the substrate surface. Heating of the substrate was provided via electron bombardment from a heated filament on the backside of the sample.
- (H 3 Ge) 4 Si compounds dissociated on the Si surface via complete H 2 elimination at 450, 400, 350 and 300 0 C 3 respectively, to produce films at growth rates of 2-3 nm/min.
- Rutherford backscattering (RBS) in random mode indicate film compositions of SiGe, SiGe 2 , SiGe 3 and SiGe 4 , respectively, in agreement with the elemental content of the Si/Ge framework of the corresponding precursors.
- the RBS channeled spectra show that the Si and Ge atoms in the structure channeled remarkably well despite the low growth temperature, which is consistent with monocrystalline materials in epitaxial alignment with the Si substrate.
- the x- ray reciprocal space map measurements showed an elongation along the "c" direction consistent with a tetragonal distortion.
- the calculated strain was in the 60-70 % range.
- Remarkably similar strain values were determined from Raman shifts of the Si-Si, Si-Ge and Ge-Ge phonon modes.
- Raman was used to investigate the distribution of strain in these SiGe layers, by measuring the phonon frequencies using laser lines with different penetration depths. The results showed that the Raman peaks did not change with depth indicating that the strain does not vary across the layers.
- the characterization of our Si-Ge materials revealed growth of crystalline, highly epitaxial, smooth, continuous and uniform alloy layers with Ge-rich concentrations and uniformly stressed or strain-relaxed microstructures.
- a key to the successful synthesis of our films is the unprecedented low growth temperatures which reduce surface mobility of the Si and Ge atoms and prevent mass segregation thereby resulting in highly uniform compositional and strain profiles at the atomic level.
- the incorporation of the entire Si-Ge molecular core promotes the formation of exceptionally uniform bonding arrangements over the entire crystal, leading to relaxed films with planar surface morphology (no surface ripples).
- FIG. 12 shows a representative AFM image of islands grown at 600 0 C using (H 3 Ge) 2 SiH 2 .
- the islands are primarily dome-shaped and reasonably uniform in size with an approximate density distribution of ⁇ 3 x 10 8 cm "2 .
- the bright field XTEM micrographs showed ensembles of coherent islands with defect free microstructure and with a narrow size distribution.
- the microstructural properties of the islands were explored via Z- contrast imaging performed on a JEOL 2010F. These experiments confirmed the presence of distinct islands grown on the substrate surface via a wetting layer of uniform thickness as shown for a representative sample produced by (H 3 Ge) 3 SiH. Note that in Z-contrast images the intensity is proportional to Z 1 ' 7 , consequently the Ge containing islands as well as the wetting layers appear considerably brighter than the underlying Si.
- FIG. 12 is also representative of the most commonly found quantum dot microstructure showing a perfectly sharp and uniform interface.
- the highly coherent nature (no defects are observed) of the quantum dots grown by our method is confirmed by the Raman spectra, which show that the islands are highly strained, as expected due to the lattice mismatch of the dots with the substrate.
- compositions of the islands were found to be SiGe 2 , SiGe 3 and SiGe 4 , reflecting the stoichiometries of the unimolecular precursors (H 3 Ge) 2 SiH 2 , (H 3 Ge) 3 SiH and (H 3 Ge) 4 Si, respectively, used for growth.
- EELS compositional profiles across the dots revealed remarkably uniform elemental distributions at the nanometer scale.
- An important advantage with regard to composition is that there is no apparent mixing of the elements across the interface as is typically observed when pure Ge islands are grown on Si at T>550°C. This type of Si interdiffudision from the substrate into Ge islands represents the most commonly reported method to form Si-Ge quantum dots on Si with Ge>50 at.%.
- FIG. 3 shows an exemplary sequence of LEEM images of SiGe 2 on Si(IOO) produced via CVD of SiH 2 (GeH 3 ) 2 , showing the layer-by-layer deposition.
- image (a) shows the morphology of the clean Si surface
- image (b) shows the deposition of the first full monolayer
- image (c) shows the second full monolayer
- image (d) shows the third full monolayer.
- the field of view is 8 mm.
- a contrast reversal in the (2 x 1) and (1 x 2) terraces is observed indicating a layer-by-layer growth. After the fourth monolayer the LEEM contrast became diffuse presumably due to new growth of incomplete layers.
- FIG. 4 is a graph showing plots of the temperature dependence of the first layer growth rates for H 3 GeSiH 3 , (H 3 Ge) 2 SiHa, (H 3 Ge) 3 SiH and (H 3 Ge) 4 Si as well as for H3GeGeH3.
- the plots show growth rates for a range of temperatures from about 420°C to about 54O 0 C and a gas pressure of about 1.0 x 10 "6 Torr.
- SiH 3 GeH 3 is essentially a compositional hybrid of (SiH 3 ) 2 and (GeH 3 ) 2 , i.e. (SiH 3 ) 2 + (GeH 3 ) 2 -> 2 (SiH 3 GeH 3 ).
- SiGe layers were accomplished via gas source MBE with a precursor flux of 5xlO '5 Torr and at a temperature of 48O 0 C. Above this temperature strained islands (quantum dots) were obtained rather than smooth layers.
- the films were examined ex situ by AFM, XRD, Raman scattering, RBS, and high-resolution XTEM. The elemental concentration, thickness and crystallinity of SiGe were determined by RBS.
- the random backscattering spectra indicate a film thickness ranging up to 100 nm and a Ge content of 50 at. % in agreement with the elemental content of the GeSi framework of the corresponding H 3 GeSiH 3 precursor.
- the aligned spectra indicated highly crystalline material in epitaxial alignment with the substrate.
- X-ray diffraction showed a single sharp peak corresponding the (004) reflection of the cubic structure.
- High resolution XRD, including reciprocal space maps of the (004) and (224) reflections revealed a partially strained layer in perfect epitaxial alignment with the substrate.
- XTEM examinations confirm crystalline and highly epitaxial growth of smooth, continuous and uniform SiGe layers.
- TEM bright field images show that films with 100 nm thicknesses are free of threading dislocations.
- a systematic survey of samples showed no defects penetrating through the layers within a field of view of - 1.5 ⁇ m in TEM micrographs.
- the upper limit of threading dislocations in this case is less that 10 5 -10 6 /cm 2 which is unusual for a material with 50 at. % Ge directly grown on Si.
- the Raman spectra showed the three main features that correspond to the "Ge-Ge", “Si-Ge” and “Si-Si” lattice vibrations at frequencies 295.8 cm “1 , 414.3 cm '1 and 497.7 cm “1 , respectively. These measured values are significantly blue shifted with respect to the expected positions for a strain free Sio. 5O Geo. 5o alloy, which are calculated to be at 293 cm “1 , 410.5 cm “1 and 492.2 cm “1 , respectively. The Raman shifts indicate that there must be a substantial residual strain in the material. Analysis of data acquired using laser lines with variable penetration depths showed that the frequencies of the Si-Si, Ge-Ge and Si-Ge phonon modes are the same throughout indicating a uniform distribution of the strain in the layers.
- FIG. 2 shows an example set of micrographs of a SiGe layer grown on a Si(IOO) substrate according to our invention.
- the top image of FIG. 2 is a bright field XTEM micrograph of the entire thickness of the SiGe layer, which shows the absence of threading defects within the field of view.
- the bottom left image shows the interface region having perfect epitaxial alignment between the Si(IOO) substrate and the SiGe layer.
- the bottom right image shows an edge dislocation close to a step region at the interface. These defects are typically located at a step on the Si surface and partially relieve the strain due to the mismatched Si and SiGe materials.
- the elemental concentration and film thickness of the SiGe 2 layers were determined by RBS in random mode.
- the crystallinity and epitaxial alignment were examined by ion channeling.
- FIG. 6 shows the random and aligned backscattering spectra for a sample grown at 48O 0 C having a film thickness of 400 run and a Ge content of 67% in perfect agreement with the Ge content of the Ge 2 Si framework of the (H 3 Ge) 2 SiH 2 compound.
- the film concentration as measured by RBS is constant with film thickness.
- the ratio of the aligned versus the random peak heights ( ⁇ m in), which measures the degree of crystallinity across the layer, is relatively low ranging from 27% at the interface to 7% near the surface.
- FIG. 6 shows the RBS spectrum of 200nm SiGe 2 film on Si(IOO). The sharp drop of the ⁇ i n value from 27% at the interface to 7% at the surface illustrates that the defects concentration decreases dramatically with increasing the film thickness.
- the XTEM images also show that the films are atomically flat which is confirmed by AFM images in contact mode.
- the as grown materials with thickness of 40 nm and 400 nm display RMS values of 0.4 nm and 1.2 nm, respectively, for areas in the range of 5X5 ⁇ m 2 to 10X10 ⁇ m 2 . These RMS values are remarkably lower than those reported previously for compositionally graded techniques ( ⁇ 30 nm) as well as other MBE methods utilizing Si and SiGe nucleation layers (-2.4 nm).
- the unstrained lattice parameter of the layer ⁇ si Ge is related to the in-plane lattice parameter ( ⁇
- siGe) and perpendicular lattice parameter (aisiGe) by the relation ⁇ siGe a ⁇ [ ⁇ —2 y (a ⁇ a ⁇ )i /a ⁇ (l + v)] in which v is the Poisson ratio of Si-Ge (0.27-0.28).
- v the Poisson ratio of Si-Ge (0.27-0.28).
- the lattice constant of a 400-nm-thick Si o . 33 Geo. 67 layer is extremely close to the values of unstrained relaxed film.
- the Raman spectrum of the Si 0 . 33 Ge 0 . 67 films (bottom) shows the characteristic peaks corresponding to Ge-Ge (296 cm “1 ), Si-Ge (407 cm “1 ) and Si-Si (478 cm “1 ) lattice vibrations. The peak positions are consistent with fully relaxed material.
- Annealing experiments were performed to establish the thermal stability of the epilayers at temperatures between 480 0 C and 750 0 C, a range well within actual device processing temperatures.
- the XRD lattice constant, the ⁇ m j n values of the RBS aligned spectra, and the AFM surface roughness were measured for the annealed samples and compared with the values of the as grown materials. Samples with a thickness of 400 nm do t not show any increase in surface roughness (rms) even after annealing at 750 0 C for 14 hours.
- FIG. 8 shows an XTEM image of a strain-free and atomically smooth SiGe 3 layer grown on Si(IOO) according to our invention. As shown in FIG. 8, defects are concentrated in the lower portion of the layers and most annihilate within 10 nm above the interface.
- FIG. 9 shows the RBS aligned spectrum of a SiGe 3 (OOl) layer grown at 38O 0 C.
- the ⁇ m i n is 25% at the SiGe/Si interface and decreases to 9% at the surface.
- the sharp peak at the interface indicates high concentration of defects which annihilate toward the surface.
- FIG. 8 showed sharp and well defined interfaces with perfectly epitaxial microstructures in which the 111 lattice planes of the film and the substrate are completely commensurate.
- the inset of FIG. 8 is an atomic resolution Z-contrast image showing a well defined, abrupt and perfectly epitaxial interface microstructure.
- the Raman spectrum of the Si o . 25 Geo. 75 films (FIG. 7 top) displays the characteristic Ge-Ge, Si-Ge and Si-Si peaks and the corresponding frequencies indicate a fully relaxed material.
- the x-ray diffraction data provided further confirmation of strain free material growth in the SiGe 3 system.
- the experimental lattice parameters matched the theoretical values which were determined using Vegard's Law.
- SiGe 4 i.e., Sio. 2O Ge o . 8O
- Si(IOO) was conducted by thermal dehydrogenation via CVD and gas source MBE of Si(GeH 3 ) 4 at 380 0 C - 300 0 C and 5xlO "6 Torr precursor pressure. Under these conditions smooth and uniform layers were obtained at reasonable growth rates of 2 nm /minute.
- the AFM RMS for all films were in the range of 1.0-1.5 nm for scans covering 5.0 ⁇ m x 5.0 ⁇ m areas.
- FIG. 10 is an XTEM image showing the atomic flat top surface of SiGe 4 film.
- FIG. 11 shows RBS random and aligned spectra (lower trace) of a Si 020 Ge 0 80 (001) layer with a thickness of 0.5 ⁇ m.
- the ion channeling data suggested that the defects are predominately concentrated at the interface while the upper portion of the film is relatively defect free.
- the XTEM bright filed images confirmed the pile up of defects at the interface and revealed highly coherent layer thickness and perfectly planar surfaces (see FIG. 10).
- XRD analysis gave the expected Vegard's values for the lattice constants indicating strain free growth as expected.
- the method of the present invention can be used to grow Si-Ge materials on substrates other than Si substrates, such as for example glass substrates.
- the facile reactivity of (H 3 Ge) 2 SiH 2 , (H 3 Ge) 3 SiH and (H 3 Ge) 4 Si paves the way to growing SiGe materials on specialty substrates that can withstand processing as high as 300 0 C, such as plastic substrates used for flexible displays.
- the method can be used to form a SiGeN layer by mixing the precursor with a nitrogen source to create the SiGeN layer.
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Priority Applications (6)
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JP2007531158A JP2008513979A (en) | 2004-09-14 | 2005-04-08 | Si-Ge semiconductor material and device growth method on a substrate |
KR1020097009014A KR101292435B1 (en) | 2004-09-14 | 2005-04-08 | Method for growing si-ge semiconductor materials and devices on substrates |
CN200580038437.3A CN101057008B (en) | 2004-09-14 | 2005-04-08 | Method for growing Si-Ge semiconductor materials and devices on substrates |
EP05746524A EP1807556A4 (en) | 2004-09-14 | 2005-04-08 | METHOD FOR GROWING Si-Ge SEMICONDUCTOR MATERIALS AND DEVICES ON SUBSTRATES |
KR1020077008535A KR101060372B1 (en) | 2004-09-14 | 2005-04-08 | Growth method of Si-Si semiconductor material and device on substrate |
US11/662,669 US8821635B2 (en) | 2004-09-14 | 2005-04-08 | Method for growing Si-Ge semiconductor materials and devices on substrates |
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US61012004P | 2004-09-14 | 2004-09-14 | |
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PCT/US2004/043854 WO2006031240A1 (en) | 2004-09-14 | 2004-12-31 | Hydride compounds with silicon and germanium core atoms and method of synthesizing same |
USPCT/US04/43854 | 2004-12-31 | ||
US66077905P | 2005-03-11 | 2005-03-11 | |
US60/660,779 | 2005-03-11 |
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Cited By (8)
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WO2007062096A2 (en) * | 2005-11-23 | 2007-05-31 | The Arizona Board Of Regents, A Body Corporate Acting On Behalf Of Arizona State University | Silicon-germanium hydrides and methods for making and using same |
WO2007062056A2 (en) * | 2005-11-23 | 2007-05-31 | The Arizona Board Of Regents, A Body Corporate Acting On Behalf Of Arizona State University | Silicon-germanium hydrides and methods for making and using same |
WO2009005862A3 (en) * | 2007-04-02 | 2009-02-26 | Univ Arizona State | Novel methods for making and using halosilylgermanes |
WO2009123926A1 (en) * | 2008-04-02 | 2009-10-08 | Arizona Board Of Regents, A Body Corporate Of The State Of Arizona Actg For & On Behalf ... | Selective deposition of sige layers from single source of si-ge hydrides |
US7915104B1 (en) | 2007-06-04 | 2011-03-29 | The Arizona Board Of Regents, A Body Corporate Of The State Of Arizona Acting For And On Behalf Of Arizona State University | Methods and compositions for preparing tensile strained Ge on Ge1-ySny buffered semiconductor substrates |
US8029905B2 (en) | 2005-03-11 | 2011-10-04 | Arizona Board Of Regents, A Body Corporate Of The State Of Arizona Acting For And On Behalf Of Arizona State University | GeSiSn-based compounds, templates, and semiconductor structures |
CN101365648B (en) * | 2005-11-23 | 2012-09-26 | 亚利桑那董事会,代表亚利桑那州立大学行事的法人团体 | Silicon-germanium hydrides and methods for making and using same |
US8288754B2 (en) | 2008-03-11 | 2012-10-16 | Nxp B.V. | Quantum-dot device and position-controlled quantum-dot-fabrication method |
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KR102326316B1 (en) | 2015-04-10 | 2021-11-16 | 삼성전자주식회사 | Semiconductor dievices and methods of manufacturing the same |
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US4910153A (en) * | 1986-02-18 | 1990-03-20 | Solarex Corporation | Deposition feedstock and dopant materials useful in the fabrication of hydrogenated amorphous silicon alloys for photovoltaic devices and other semiconductor devices |
US4777023A (en) * | 1986-02-18 | 1988-10-11 | Solarex Corporation | Preparation of silicon and germanium hydrides containing two different group 4A atoms |
US7594967B2 (en) * | 2002-08-30 | 2009-09-29 | Amberwave Systems Corporation | Reduction of dislocation pile-up formation during relaxed lattice-mismatched epitaxy |
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Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
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US8029905B2 (en) | 2005-03-11 | 2011-10-04 | Arizona Board Of Regents, A Body Corporate Of The State Of Arizona Acting For And On Behalf Of Arizona State University | GeSiSn-based compounds, templates, and semiconductor structures |
US8133802B2 (en) | 2005-11-23 | 2012-03-13 | Arizona Board Of Regents | Silicon-germanium hydrides and methods for making and using same |
US8216537B2 (en) | 2005-11-23 | 2012-07-10 | Arizona Board Of Regents | Silicon-germanium hydrides and methods for making and using same |
WO2007062056A3 (en) * | 2005-11-23 | 2007-10-04 | Univ Arizona State | Silicon-germanium hydrides and methods for making and using same |
US8524582B2 (en) | 2005-11-23 | 2013-09-03 | The Arizona Board Of Regents | Silicon-germanium hydrides and methods for making and using same |
US8518360B2 (en) | 2005-11-23 | 2013-08-27 | Arizona Board Of Regents, A Corporate Body Organized Under Arizona Law, Acting On Behalf Of Arizona State University | Silicon-germanium hydrides and methods for making and using same |
CN101365648B (en) * | 2005-11-23 | 2012-09-26 | 亚利桑那董事会,代表亚利桑那州立大学行事的法人团体 | Silicon-germanium hydrides and methods for making and using same |
WO2007062056A2 (en) * | 2005-11-23 | 2007-05-31 | The Arizona Board Of Regents, A Body Corporate Acting On Behalf Of Arizona State University | Silicon-germanium hydrides and methods for making and using same |
WO2007062096A3 (en) * | 2005-11-23 | 2007-08-02 | Univ Arizona State | Silicon-germanium hydrides and methods for making and using same |
WO2007062096A2 (en) * | 2005-11-23 | 2007-05-31 | The Arizona Board Of Regents, A Body Corporate Acting On Behalf Of Arizona State University | Silicon-germanium hydrides and methods for making and using same |
US8043980B2 (en) | 2007-04-02 | 2011-10-25 | Arizona Board of Regents, a body corporate acting for and on behalf of Arizona State University | Methods for making and using halosilylgermanes |
WO2009005862A3 (en) * | 2007-04-02 | 2009-02-26 | Univ Arizona State | Novel methods for making and using halosilylgermanes |
US7915104B1 (en) | 2007-06-04 | 2011-03-29 | The Arizona Board Of Regents, A Body Corporate Of The State Of Arizona Acting For And On Behalf Of Arizona State University | Methods and compositions for preparing tensile strained Ge on Ge1-ySny buffered semiconductor substrates |
US8288754B2 (en) | 2008-03-11 | 2012-10-16 | Nxp B.V. | Quantum-dot device and position-controlled quantum-dot-fabrication method |
WO2009123926A1 (en) * | 2008-04-02 | 2009-10-08 | Arizona Board Of Regents, A Body Corporate Of The State Of Arizona Actg For & On Behalf ... | Selective deposition of sige layers from single source of si-ge hydrides |
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WO2006031257A3 (en) | 2006-09-08 |
EP1807556A2 (en) | 2007-07-18 |
KR101060372B1 (en) | 2011-08-29 |
KR20070083681A (en) | 2007-08-24 |
EP1807556A4 (en) | 2011-03-02 |
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