Heteroepitaxial growth of thick α-Ga_2O_3 film on sapphire(0001)by MIST-CVD technique
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摘要
The 8 μm thick single-crystalline α-Ga2O3 epilayers have been heteroepitaxially grown on sapphire(0001) substrates via mist chemical vapor deposition technique. High resolution X-ray diffraction measurements show that the full-widths-at-halfmaximum(FWHM) of rocking curves for the(0006) and(10-14) planes are 0.024° and 0.24°, and the corresponding densities of screw and edge dislocations are 2.24 × 106 and 1.63 × 109 cm-2, respectively, indicative of high single crystallinity. The out-ofplane and in-plane epitaxial relationships are [0001] α-Ga2O3//[0001] α-Al2O3 and [11-20] α-Ga2O3//[11-20] α-Al2O3, respectively.The lateral domain size is in micron scale and the indirect bandgap is determined as 5.03 eV by transmittance spectra. Raman measurement indicates that the lattice-mismatch induced compressive residual strain cannot be ruled out despite the large thickness of the α-Ga2O3 epilayer. The achieved high quality α-Ga2O3 may provide an alternative material platform for developing high performance power devices and solar-blind photodetectors.
The 8 μm thick single-crystalline α-Ga2O3 epilayers have been heteroepitaxially grown on sapphire(0001) substrates via mist chemical vapor deposition technique. High resolution X-ray diffraction measurements show that the full-widths-at-halfmaximum(FWHM) of rocking curves for the(0006) and(10-14) planes are 0.024° and 0.24°, and the corresponding densities of screw and edge dislocations are 2.24 × 106 and 1.63 × 109 cm-2, respectively, indicative of high single crystallinity. The out-ofplane and in-plane epitaxial relationships are [0001] α-Ga2O3//[0001] α-Al2O3 and [11-20] α-Ga2O3//[11-20] α-Al2O3, respectively.The lateral domain size is in micron scale and the indirect bandgap is determined as 5.03 eV by transmittance spectra. Raman measurement indicates that the lattice-mismatch induced compressive residual strain cannot be ruled out despite the large thickness of the α-Ga2O3 epilayer. The achieved high quality α-Ga2O3 may provide an alternative material platform for developing high performance power devices and solar-blind photodetectors.
The 8 μm thick single-crystalline α-Ga2O3 epilayers have been heteroepitaxially grown on sapphire(0001) substrates via mist chemical vapor deposition technique. High resolution X-ray diffraction measurements show that the full-widths-at-halfmaximum(FWHM) of rocking curves for the(0006) and(10-14) planes are 0.024° and 0.24°, and the corresponding densities of screw and edge dislocations are 2.24 × 106 and 1.63 × 109 cm-2, respectively, indicative of high single crystallinity. The out-ofplane and in-plane epitaxial relationships are [0001] α-Ga2O3//[0001] α-Al2O3 and [11-20] α-Ga2O3//[11-20] α-Al2O3, respectively.The lateral domain size is in micron scale and the indirect bandgap is determined as 5.03 eV by transmittance spectra. Raman measurement indicates that the lattice-mismatch induced compressive residual strain cannot be ruled out despite the large thickness of the α-Ga2O3 epilayer. The achieved high quality α-Ga2O3 may provide an alternative material platform for developing high performance power devices and solar-blind photodetectors.
引文
[1]Varley J B, Weber J R, Janotti A, et al. Oxygen vacancies and donor impurities inβ-Ga2O3. Appl Phys Lett, 2010, 97(14), 142106
[2]Higashiwaki M, Sasaki K, Kuramata A, et al. Gallium oxide(Ga2O3)metal–semiconductor field-effect transistors on single-crystalβ-Ga2O3(010)substrates. Appl Phys Lett, 2012, 100(1), 013504
[3]Playford H Y, Hannon A C, Barney E R, et al. Structures of uncharacterised polymorphs of gallium oxide from total neutron diffraction. Chemistry, 2013, 19(8), 2803
[4]Roy R, Hill V G, Osborn E F. Polymorphism of Ga2O3 and the System Ga2O3–H2O. J Am Chem Soc, 1952, 74(3), 719
[5]Aida H, Nishiguchi K, Takeda H, et al. Growth ofβ-Ga2O3 single crystals by the edge-defined, film fed growth method. Jpn J Appl Phys, 2008, 47(11), 8506
[6]Mahmoud W E. Solar blind avalanche photodetector based on the cation exchange growth ofβ-Ga2O3/SnO2 bilayer heterostructure thin film. Sol Energy Mater Sol Cells, 2016, 152, 65
[7]Guo D Y, Shi H Z, Qian Y P, et al. Fabrication ofβ-Ga2O3/ZnO heterojunction for solar-blind deep ultraviolet photodetection.Semicond Sci Technol, 2017, 32(3), 03LT01
[8]Zhao X, Wu Z, Guo D, et al. Growth and characterization ofα-phase Ga2-x Snx O3 thin films for solar-blind ultraviolet applications. Semicond Sci Technol, 2016, 31(6), 065010
[9]Chen X, Xu Y, Zhou D, et al. Solar-blind photodetector with high avalanche gains and bias-tunable detecting functionality based on metastable phase alpha-Ga2O3/ZnO isotype heterostructures.ACS Appl Mater Interfaces, 2017, 9(42), 36997
[10]Li J, Chen X, Ma T, et al. Identification and modulation of electronic band structures of single-phaseβ-(Alx Ga1-x)2O3 alloys grown by laser molecular beam epitaxy. Appl Phys Lett, 2018,113(4), 041901
[11]Zhao B, Wang F, Chen H, et al. Solar-blind avalanche photodetector based on single ZnO–Ga2O3 core-shell microwire. Nano Lett, 2015, 15(6), 3988
[12]Sasaki K, Higashiwaki M, Kuramata A, et al. Ga2O3 Schottky barrier diodes fabricated by using single-crystalβ-Ga2O3(010)substrates. IEEE Electron Device Lett, 2013, 34(4), 493
[13]Akaiwa K, Fujita S. Electrical conductive corundum-structuredα-Ga2O3 thin films on sapphire with tin-doping grown by spray-assisted mist chemical vapor deposition. J Jpn J Appl Phys, 2012,51, 070203
[14]Ito H, Kaneko K, Fujita S. Growth and band gap control of corundum-structuredα-Ga2O3 thin films on sapphire by spray-assisted mist chemical vapor deposition. Jpn J Appl Phys, 2012, 51,100207
[15]Kaneko K, Nomura T, Kakeya I, et al. Fabrication of highly crystalline corundum-structuredα-(Ga1-x Fex)2O3 alloy thin films on sapphire substrates. Appl Phys Express, 2009, 2, 075501
[16]Sun H, Li K H, Castanedo C G T, et al. HCl flow-induced phase change ofα-,β-, andε-Ga2O3 films grown by MOCVD. Cryst Growth Des, 2018, 18(4), 2370
[17]Yao Y, Okur S, Lyle L A M, et al. Growth and characterization ofα-,β-, and?-phases of Ga2O3 using MOCVD and HVPE techniques.Mater Res Lett, 2018, 6(5), 268
[18]Kumaran R, Tiedje T, Webster S E, et al. Epitaxial Nd-doped alpha-(Al(1-x)Ga(x))2O3 films on sapphire for solid-state waveguide lasers. Opt Lett, 2010, 35(22), 3793
[19]Fujita S, Oda M, Kaneko K, et al. Evolution of corundum-structured III-oxide semiconductors:Growth, properties, and devices.Jpn J Appl Phys, 2016, 55(12), 1202A3
[20]Oda M, Kaneko K, Fujita S, et al. Crack-free thick(~5μm)α-Ga2O3films on sapphire substrates withα-(Al,Ga)2O3 buffer layers. Jpn J Appl Phys, 2016, 55(12), 1202B4
[21]Shinohara D, Fujita S. Heteroepitaxy of corundum-structuredα-Ga2O3 thin films onα-Al2O3 substrates by ultrasonic mist chemical vapor deposition. Jpn J Appl Phys, 2008, 47(9), 7311
[22]Kawaharamura T. Physics on development of open-air atmospheric pressure thin film fabrication technique using mist droplets:Control of precursor flow. Jpn J Appl Phys, 2014, 53(5),05FF08
[23]Moram M A, Vickers M E. X-ray diffraction of III-nitrides. Rep Prog Phys, 2009, 72(3), 036502
[24]Zheng X H, Chen H, Yan Z B, et al. Determination of twist angle of in-plane mosaic spread of GaN films by high-resolution X-ray diffraction. J Cryst Growth, 2003, 255(1/2), 63
[25]Kaneko K, Kawanowa H, Ito H, et al. Evaluation of misfit relaxation inα-Ga2O3 epitaxial growth onα-Al2O3 substrate. Jpn J Appl Phys, 2012, 51, 020201
[26]Davis E A, Mott N F, et al. Conduction in non-crystalline systems V. Conductivity, optical absorption and photoconductivity in amorphous semiconductors. Philos Mag A, 1970, 22(179), 0903
[27]Cusco R, Domenech-Amador N, Hatakeyama T, et al. Lattice dynamics of a mist-chemical vapor deposition-grown corundumlike Ga2O3 single crystal. J Appl Phys, 2015, 117(18), 185706
[2]Higashiwaki M, Sasaki K, Kuramata A, et al. Gallium oxide(Ga2O3)metal–semiconductor field-effect transistors on single-crystalβ-Ga2O3(010)substrates. Appl Phys Lett, 2012, 100(1), 013504
[3]Playford H Y, Hannon A C, Barney E R, et al. Structures of uncharacterised polymorphs of gallium oxide from total neutron diffraction. Chemistry, 2013, 19(8), 2803
[4]Roy R, Hill V G, Osborn E F. Polymorphism of Ga2O3 and the System Ga2O3–H2O. J Am Chem Soc, 1952, 74(3), 719
[5]Aida H, Nishiguchi K, Takeda H, et al. Growth ofβ-Ga2O3 single crystals by the edge-defined, film fed growth method. Jpn J Appl Phys, 2008, 47(11), 8506
[6]Mahmoud W E. Solar blind avalanche photodetector based on the cation exchange growth ofβ-Ga2O3/SnO2 bilayer heterostructure thin film. Sol Energy Mater Sol Cells, 2016, 152, 65
[7]Guo D Y, Shi H Z, Qian Y P, et al. Fabrication ofβ-Ga2O3/ZnO heterojunction for solar-blind deep ultraviolet photodetection.Semicond Sci Technol, 2017, 32(3), 03LT01
[8]Zhao X, Wu Z, Guo D, et al. Growth and characterization ofα-phase Ga2-x Snx O3 thin films for solar-blind ultraviolet applications. Semicond Sci Technol, 2016, 31(6), 065010
[9]Chen X, Xu Y, Zhou D, et al. Solar-blind photodetector with high avalanche gains and bias-tunable detecting functionality based on metastable phase alpha-Ga2O3/ZnO isotype heterostructures.ACS Appl Mater Interfaces, 2017, 9(42), 36997
[10]Li J, Chen X, Ma T, et al. Identification and modulation of electronic band structures of single-phaseβ-(Alx Ga1-x)2O3 alloys grown by laser molecular beam epitaxy. Appl Phys Lett, 2018,113(4), 041901
[11]Zhao B, Wang F, Chen H, et al. Solar-blind avalanche photodetector based on single ZnO–Ga2O3 core-shell microwire. Nano Lett, 2015, 15(6), 3988
[12]Sasaki K, Higashiwaki M, Kuramata A, et al. Ga2O3 Schottky barrier diodes fabricated by using single-crystalβ-Ga2O3(010)substrates. IEEE Electron Device Lett, 2013, 34(4), 493
[13]Akaiwa K, Fujita S. Electrical conductive corundum-structuredα-Ga2O3 thin films on sapphire with tin-doping grown by spray-assisted mist chemical vapor deposition. J Jpn J Appl Phys, 2012,51, 070203
[14]Ito H, Kaneko K, Fujita S. Growth and band gap control of corundum-structuredα-Ga2O3 thin films on sapphire by spray-assisted mist chemical vapor deposition. Jpn J Appl Phys, 2012, 51,100207
[15]Kaneko K, Nomura T, Kakeya I, et al. Fabrication of highly crystalline corundum-structuredα-(Ga1-x Fex)2O3 alloy thin films on sapphire substrates. Appl Phys Express, 2009, 2, 075501
[16]Sun H, Li K H, Castanedo C G T, et al. HCl flow-induced phase change ofα-,β-, andε-Ga2O3 films grown by MOCVD. Cryst Growth Des, 2018, 18(4), 2370
[17]Yao Y, Okur S, Lyle L A M, et al. Growth and characterization ofα-,β-, and?-phases of Ga2O3 using MOCVD and HVPE techniques.Mater Res Lett, 2018, 6(5), 268
[18]Kumaran R, Tiedje T, Webster S E, et al. Epitaxial Nd-doped alpha-(Al(1-x)Ga(x))2O3 films on sapphire for solid-state waveguide lasers. Opt Lett, 2010, 35(22), 3793
[19]Fujita S, Oda M, Kaneko K, et al. Evolution of corundum-structured III-oxide semiconductors:Growth, properties, and devices.Jpn J Appl Phys, 2016, 55(12), 1202A3
[20]Oda M, Kaneko K, Fujita S, et al. Crack-free thick(~5μm)α-Ga2O3films on sapphire substrates withα-(Al,Ga)2O3 buffer layers. Jpn J Appl Phys, 2016, 55(12), 1202B4
[21]Shinohara D, Fujita S. Heteroepitaxy of corundum-structuredα-Ga2O3 thin films onα-Al2O3 substrates by ultrasonic mist chemical vapor deposition. Jpn J Appl Phys, 2008, 47(9), 7311
[22]Kawaharamura T. Physics on development of open-air atmospheric pressure thin film fabrication technique using mist droplets:Control of precursor flow. Jpn J Appl Phys, 2014, 53(5),05FF08
[23]Moram M A, Vickers M E. X-ray diffraction of III-nitrides. Rep Prog Phys, 2009, 72(3), 036502
[24]Zheng X H, Chen H, Yan Z B, et al. Determination of twist angle of in-plane mosaic spread of GaN films by high-resolution X-ray diffraction. J Cryst Growth, 2003, 255(1/2), 63
[25]Kaneko K, Kawanowa H, Ito H, et al. Evaluation of misfit relaxation inα-Ga2O3 epitaxial growth onα-Al2O3 substrate. Jpn J Appl Phys, 2012, 51, 020201
[26]Davis E A, Mott N F, et al. Conduction in non-crystalline systems V. Conductivity, optical absorption and photoconductivity in amorphous semiconductors. Philos Mag A, 1970, 22(179), 0903
[27]Cusco R, Domenech-Amador N, Hatakeyama T, et al. Lattice dynamics of a mist-chemical vapor deposition-grown corundumlike Ga2O3 single crystal. J Appl Phys, 2015, 117(18), 185706