# Fileset

[Figures181210.pdf](https://mdr.nims.go.jp/filesets/596bdf48-29ad-45de-addb-d6bee20fcc58/download)

## Creator

[大島祐一](https://orcid.org/0000-0001-8293-4891)

## Rights

[In Copyright](http://rightsstatements.org/vocab/InC/1.0/)

## Other metadata

[Halide Vapor Phase Epitaxy 2—Heteroepitaxial Growth of α- and ɛ-Ga2O3](https://mdr.nims.go.jp/datasets/5328de98-3a42-402f-b688-47c36fa5dc4b)

## Fulltext

PowerPoint プレゼンテーションFigure 1Ga-meltGaClexhaustN2SubstrateHClO2HeaterQuartz tubeDopantSchematic illustration of an HVPE reactor for Ga2O3 .Figure 2Growth rate of -Ga2O3 as a function of growth temperature.500 550 600 65000.20.40.60.81.0Tg [oC]Growth rate [normalized]Figure 30 2 4 6050100150P(O2) [kPa]Growth rate [m/h]P(HCl) = 0.25 kPa0 0.3 0.6 0.9P(HCl) [kPa]P(O2) = 4.0 kPa(a) (b)Growth rate of -Ga2O3 as functions of (a) O2 partial pressure and (b) HCl partial pressure. [8]Figure 4(a)Photographs of Ga2O3 films grown at (a) 650oC, (b) 600oC, (c) 575oC, and (d) 550oC.(b) (c) (d)Figure 520 40 60 80 1002 [deg.]Intensity [arb. units]38 39 40 41 42 432 [deg.]Intensity [arb. units]-Ga2O30006Sapphire 0006-Ga2O30006Sapphire 0006-Ga2O300012(a) (b)Sapphire00012XRD 2– profiles of an -Ga2O3 layer: (a) wide-scan profile and (b) narrow-scan profile near 0006 diffraction. [8]Figure 6-Ga2O3Sapphire(b)(a)SEM images of an -Ga2O3 layer: (a) surface image and (b) cross-sectional image. [8]Figure 7=20°=40°=60°(a) (b)10-1 104cps10-1 103cps100 101 102100 101 102 103X-ray 10ത12 pole figures (log scale) of (a) -Ga2O3 layer and (b) sapphire substrate.Figure 8-1.0 -0.5 0 0.5 1.0 [deg]Intensity [normalized]0006922 arcsec1298 arcsecXRCs of a conventional -Ga2O3 film grown by HVPE [8].10ത12Figure 91 m 500 nm(a) (b)[11ത20][11ത20]TEM images of a conventional -Ga2O3 film grown by HVPE: (a) cross-sectional image and (b) plan-view image.Figure 103 4 5020406080100Photon energy [eV]Transmittance [%]5.0 5.1 5.200.20.40.60.81.0Photon energy [eV](h)2 [1010eV2cm-2]Transmittance spectra of -Ga2O3. The inset shows the absorption coefficient in (h)2 vs. h.Figure 1136 37 38 39 40 41 422 [deg.]Intensity [arb. units (log-scale)]600C575C550C525C500C450C400C300C200CRTPt 111-Ga2O3 0006-Ga2O3 401Sapphire0006XRD 2– scan profiles for an HVPE-grown -Ga2O3 film measured at RT and elevated temperatures.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.010151016101710181019Depth [m]Concentration [cm-3]HCSiClGeFigure 12SIMS depth profile of a Ge-doped -Ga2O3 film. The arrows indicate the detection limits.Figure 130 2 4 6 8 100123GeCl4 bubbling rate [sccm]Ge concentration [1019 cm-3]Ge concentration in -Ga2O3 as a function of GeCl4 bubbling rate.1017 1018 1019 1020010203040Mobility [cm2V-1s-1]Carrier concentration [cm-3]Figure 140 2 4 6 8 10 1201234GeCl4 bubbling rate [sccm]Carrier concentration [1019 cm-3]0 2 4 6 8 10 120102030GeCl4 bubbling rate [sccm]Mobility [cm2V-1s-1](a) (b) mist-CVD,Sn-doped [20]*This work(c)(a) Carrier concentration and (b) electron mobility at RT as functions of GeCl4 bubbling rate. (c) Relationship between electron mobility and carrier concentration at RT for Ge-doped -Ga2O3. Data from the literature [20] are also shown for comparison.Figure 15300 400 500 600051015202530T [K]Mobility [cm2V-1s-1]1.5 2.0 2.5 3.0 3.510191020 3004005006001000/T [K-1]Carrier concentration [cm-3]T [K]3 sccm6 sccm10 sccm3 sccm6 sccm10 sccm(a) Carrier concentration and (b) electron mobility as functions of temperature.(a) (b)Figure 16(b)(d) (e)(a)DislocationProcedure of FIELO technique.(c)Mask(f)Seed layerSubstrateFigure 17(a)20 m 20 m 20 m(b) (c)[11ത20]SEM images of -Ga2O3 islands grown on dot-patterned mask with window spacings of (a) 5 µm, (b) 10 µm, and (c) 20 µm (bird’s eye view) [21].(a)Figure 1820 m 20 m(b)[11ത20]SEM images of -Ga2O3 islands grown at nominal growth rates of (a) 7 µm/h and (b) 5 µm/h (bird’s eye view) [21].5 m(0001)Figure 19(10ത11)(11ത20)(10ത14)5 m 5 m[11ത20](a) (b) (c)SEM images of -Ga2O3 islands grown at (a) 540C, (b) 500C, and (c) 460C (bird’s eye view) [21].Figure 20(a) (b) (c) (d)5 m5 m 5 m 5 m5 m5 m 5 m 5 m[11ത20]SEM images of -Ga2O3 islands with nominal thickness of (a) 0.5 µm, (b) 1.6 µm, (c) 8 µm, and (d) 12 µm (plan-view and bird’s eye view) [21].Figure 210 5 10 15030060090012001500Nominal thickness[ m]XRC FWHM [arcsec]            (Twist) 0006  (Tilt)10ത12XRC FWHMs of ELO-grown -Ga2O3 as a function of nominal thickness [21].-1.0 -0.5 0 0.5 1.0 [deg]Intensity [normalized]Figure 22000610ത12XRC profiles of ELO-grown -Ga2O3 with nominal thickness of 12 µm [21].Figure 232 m 2 m(a) (b)Cross-sectional TEM images of -Ga2O3 islands grown at (a) 540oC and (b) 460oC.[11ത20]Figure 241 m[10ത10]Plan-view TEM image of -Ga2O3 stripes with well-developed (0001) plane [21].Figure 25MaskWindowCoalesced boundarySapphire-Ga2O3Coalesced boundaryWindow position5 m(a)(b)MaskWindow(c)3 m [11ത20][11ത20](a) Plan-view SEM image of a coalesced -Ga2O3 film. (b) Schematic illustration of the cross section. (c) Cross-sectional TEM image of the film [21].20 30 40 50 60 70 80 90 1002 [deg.]Intensity [arb. units]Figure 26-Ga2O30004-Ga2O30006-Ga2O30008GaN 0002GaN 0004AlN0002AlN00046H-SiC 000126H-SiC 0006(a)(b)XRD –2 scan profiles of -Ga2O3 layers grown on (a) (0001) GaN and (b) (0001) AlN[9].Figure 27(a)(c)30 m30 m(b)(d)30 m30 m(c)(f)(0001) GaN (0001) AlN2min7minPlan-view SEM images of -Ga2O3 layers grown on (0001) GaN and (0001) AlN with growth times of 2 and 7 min [9].Figure 28GaN-Ga2O31 m 1 m(a) (b)Cross-sectional SEM images of -Ga2O3 layers grown on (0001) GaN with growth times of (a) 2 min and (b) 7 min [9].Figure 29=20°=40°=60°(a) (b)104cps100 101 102 103103cps100 101 102X-ray pole figures (log scale) of (a) -Ga2O3 10ത14 and (b) GaN 10ത12 [9].-2 -1 0 1 2 [deg.]Intensity [arb. units]Figure 30(a)(b)0.67° 1.17°0.61° 1.21°0004 10ത11XRCs of -Ga2O3 layers grown on (a) (0001) GaN and (b) (0001) AlN [9].Figure 312 3 4 5020406080Photon energy [eV]Transmittance [%]4.0 4.5 5.0 5.501234Photon energy [eV](h)2 [1011eV2cm-2]Transmittance spectrum of -Ga2O3. The inset shows the absorption coefficient in (h)2 vs. h [9].Figure 3232 34 36 38 40 422 [deg.]Intensity [arb. units (log-scale)]825C800C775C750C725C700C600C400C200CRTGaN 0002 -Ga2O3 0004-Ga2O3 401Pt 111XRD2– scan profiles for an HVPE-grown -Ga2O3 film measured at RT and elevated temperatures [9].