共查询到20条相似文献,搜索用时 46 毫秒
1.
V. Avrutin Ü. Özgür S. Chevtchenko C. Litton H. Morkoç 《Journal of Electronic Materials》2007,36(4):483-487
We report on the optical and magnetic properties of the magnetic semiconductor Zn(V)O fabricated by implantation of 195 keV
51V+ ions into bulk ZnO:Al grown by a hydrothermal technique. Two sets of the samples, containing N
d
–N
a
∼ 1015 cm−3 and 1018 cm−3, were implanted to doses of 1 × 1015 cm−2, 3 × 1015 cm−2, and 1 × 1016 cm−2. The ion implantation was performed at 573 K. To remove irradiation-induced defects, the samples were annealed in air at
1073 K. Photoluminescence (PL) measurements of Zn(V)O films were carried out at temperatures from 10 K to 300 K. The effects
of implantation dose and free carrier concentration on the magnetic properties of Zn(V)O were studied using a superconducting
quantum interference device magnetometer. Ferromagnetism has been observed in annealed highly conductive samples implanted
to 1 × 1016 cm−2. The PL studies of ZnO bulk samples implanted with V+ have revealed that thermal annealing at 1073 K restores to a large extent the optical quality of the material. A new emission
line centered at 3.307 eV has been found in the PL spectrum of the highly conductive samples implanted to the dose of 1 × 1016 cm−2, which is most probably due to complexes involving V ions. 相似文献
2.
Electrical activation studies of Al
x
Ga1−x
N (x = 0.45 and 0.51) implanted with Si for n-type conductivity have been made as a function of ion dose and anneal temperature. Silicon ions were implanted at 200 keV
with doses ranging from 1 × 1014 cm−2 to 1 × 1015 cm−2 at room temperature. The samples were subsequently annealed from 1150°C to 1350°C for 20 min in a nitrogen environment. Nearly
100% electrical activation efficiency was successfully obtained for the Si-implanted Al0.45Ga0.55N samples after annealing at 1350°C for doses of 1 × 1014 cm−2 and 5 × 1014 cm−2 and at 1200°C for a dose of 1 × 1015 cm−2, and for the Al0.51Ga0.49N implanted with silicon doses of 1 × 1014 cm−2 and 5 × 1014 cm−2 after annealing at 1300°C. The highest room-temperature mobility obtained was 61 cm2/V s and 55 cm2/V s for the low-dose implanted Al0.45Ga0.55N and Al0.51Ga0.49N, respectively, after annealing at 1350°C for 20 min. These results show unprecedented activation efficiencies for Al
x
Ga1−x
N with high Al mole fractions and provide suitable annealing conditions for Al
x
Ga1−x
N-based device applications. 相似文献
3.
The physical and electrical properties of BF
2
+
implanted polysilicon films subjected to rapid thermal annealing (RTA) are presented. It is found that the out diffusion
ofF and its segregation at polysilicon/silicon oxide interface during RTA are the major causes ofF anomalous migration. Fluorine bubbles were observed in BF
2
+
implanted samples at doses of 1×1015 and 5×1015 cm−2 after RTA. 相似文献
4.
E.A. Moore Y.K. Yeo G.J. Gruen Mee-Yi Ryu R.L. Hengehold 《Journal of Electronic Materials》2010,39(1):21-28
Electrical activation studies were carried out on Si-implanted Al0.33Ga0.67N as a function of ion dose, annealing temperature, and annealing time. The samples were implanted at room temperature with
Si ions at 200 keV in doses ranging from 1 × 1014 cm−2 to 1 × 1015 cm−2, and subsequently proximity-cap annealed from 1150°C to 1350°C for 20 min to 60 min in a nitrogen environment. One hundred
percent electrical activation efficiency was obtained for Al0.33Ga0.67N samples implanted with a dose of 1 × 1015 cm−2 after annealing at either 1200°C for 40 min or at 1300°C for 20 min. The samples implanted with doses of 1 × 1014 cm−2 and 5 × 1014 cm−2 exhibited significant activations of 74% and 90% after annealing for 20 min at 1300°C and 1350°C, respectively. The mobility
increased as the annealing temperature increased from 1150°C to 1350°C, showing peak mobilities of 80 cm2/V s, 64 cm2/V s, and 61 cm2/V s for doses of 1 × 1014 cm−2, 5 × 1014 cm−2, and 1 × 1015 cm−2, respectively. Temperature-dependent Hall-effect measurements showed that most of the implanted layers were degenerately
doped. Cathodoluminescence measurements for all samples exhibited a sharp neutral donor-bound exciton peak at 4.08 eV, indicating
excellent recovery of damage caused by ion implantation. 相似文献
5.
Mee-Yi Ryu Y. K. Yeo M. A. Marciniak T. W. Zens E. A. Moore R. L. Hengehold T. D. Steiner 《Journal of Electronic Materials》2006,35(4):647-653
Electrical and optical activation studies of lower dose Si-implanted AlxGa1?xN (x=0.14 and 0.24) have been made systematically as a function of ion dose and anneal temperature. Silicon ions were implanted at 200 keV with doses ranging from 1×1013 cm?2 to 1×1014 cm?2 at room temperature. The samples were proximity cap annealed from 1,100°C to 1,350°C with a 500-Å-thick AlN cap in a nitrogen environment. Nearly 100% electrical activation efficiency was obtained for Al0.24Ga0.76N implanted with a dose of 1 × 1014 cm?2 after annealing at an optimum temperature around 1,300°C, whereas for lower dose (≤5×1013 cm?2) implanted Al0.24Ga0.76N samples, the electrical activation efficiencies continue to increase with anneal temperature up through 1,350°C. Seventy-six percent electrical activation efficiency was obtained for Al0.14Ga0.86N implanted with a dose of 1 × 1014 cm?2 at an optimum anneal temperature of around 1,250°C. The highest mobilities obtained were 89 cm2/Vs and 76 cm2/Vs for the Al0.14Ga0.86N and Al0.24Ga0.76N, respectively. Consistent with the electrical results, the photoluminescence (PL) intensity of the donor-bound exciton peak increases as the anneal temperature increases from 1,100°C to 1,250°C, indicating an increased implantation damage recovery with anneal temperature. 相似文献
6.
Tao Yang Shanliang Chen Xiaoxiao Li Xiaojie Xu Fengmei Gao Lin Wang Junhong Chen Weiyou Yang Xinmei Hou Xiaosheng Fang 《Advanced functional materials》2019,29(11)
In the present work, high‐performance photodetectors (PDs) based on a single B‐doped 3C‐SiC nanobelt, which are synthesized via catalyst‐free pyrolysis of polymeric precursors of polysilazane, are reported. The as‐built PDs have a high responsivity and external quantum efficiency of 6.37 × 105 A · W?1 and 2.0 × 108% under 405 nm light with a power density of 0.14 mW · cm?2 at 5 V, respectively. The detectivity of the PDs is measured to be of 6.86 × 1014 Jones. Moreover, the B‐doped 3C‐SiC nanobelt PDs exhibit a long‐term stability against 300 °C up to 180 days, suggesting their promising applications to be served under harsh conditions. 相似文献
7.
A. V. Karimov A. Z. Rakhmatov S. P. Skorniakov D. M. Yodgorova A. A. Karimov Sh. M. Kuliev 《Radioelectronics and Communications Systems》2017,60(6):272-274
There are carried out experimental researches of dependence of drop of direct voltage of current-voltage characteristics of the silicone power diode on electrons radiation dose. It is stated that dose increase from 2×1014 to 2×1015 Φe/cm2 results in direct voltage drop on the diode increases monotonically, and the lifetime of the minority charge carriers decreases by a factor of ten. It is shown the dominating role of decrease of minority charge carriers density in the base together with majority charge carries lifetime at forming of current-voltage characteristics of after irradiation by electrons. 相似文献
8.
N.G. Rudawski L.R. Whidden V. Craciun K.S. Jones 《Journal of Electronic Materials》2009,38(9):1926-1930
Amorphization and solid-phase epitaxial growth were studied in C-cluster ion-implanted Si. C7H7 ions were implanted at a C-equivalent energy of 10 keV to C doses of 0.1 × 1015 cm−2 to 8.0 × 1015 cm−2 into (001) Si wafers. Transmission electron microscopy revealed a C amorphizing dose of ~5.0 × 1014 cm−2. Annealing of amorphized specimens to effect solid-phase epitaxial growth resulted in defect-free growth for C doses of 0.5 × 1015 cm−2 to 1.0 × 1015 cm−2. At higher doses, growth was defective and eventually polycrystalline due to induced in-plane tensile stress from substitutional
C incorporation. 相似文献
9.
B. M. Arora J. M. Castillo M. B. Kurup R. P. Sharma 《Journal of Electronic Materials》1981,10(5):845-862
Samples of silicon single crystals implanted with 3 × 1014/ cm2, 1 × 1015/cm2 and 6 × 1015/cm2 Ga ions have been investigated by alpha particle back-scattering before and after annealing, differential Hall effect and
ellipsometry measurements. The impurity depth profiles as obtained from the analysis of the back-scattering spectra do not
show any long tail of Ga atoms even in the high dose as-implanted samples. Upon annealing, the dopant atom distributions are
seen to be modified during recrystallization. High levels of electrical activation of Ga atoms (~3 × 1020 cm-3), exceeding the maximum solid solubility limit of Ga in Si (4.5 × 1019 cm-3) and comparable to those obtained by laser annealing have been achieved by conventional thermal annealing. The above three
measurements have clearly shown that there is 20% residual damage in the high dose (6 × 1015 cm2) implanted sample after the recrystallization at about 570°C. This may be related to strain in the lattice at the high concentrations
of metastable substitutional Ga atoms. Annealing at higher temperatures reduces the electrical activity of Ga atoms, possibly
by driving out the metastable high substitutional concentrations of Ga atoms into electrically inactive clusters or precipitates. 相似文献
10.
Electrical activation studies of Si-implanted Al
x
Ga1−x
N with an Al mole fraction of 11% to 51% have been carried out as a function of ion dose and annealing temperature. The Al
x
Ga1−x
N samples were implanted at room temperature with Si ions at 200 keV in doses ranging from 1 × 1014 cm−2 to 1 × 1015 cm−2, and subsequently annealed from 1100°C to 1350°C for 20 min in a nitrogen environment. The maximum electrical activation
efficiencies for the Al
x
Ga1−x
N samples with an Al mole fraction less than 40% were obtained for samples implanted with the highest Si dose of 1 × 1015 cm−2. On the other hand, for the Al
x
Ga1−x
N samples with an Al mole fraction more than 40%, nearly perfect activation efficiencies of 99% and 100% were obtained for
the samples implanted with the lowest Si dose of 1 × 1014 cm−2. The mobility of the Si-implanted Al
x
Ga1−x
N samples increased with increasing annealing temperature in spite of the increased number of ionized donors and thus increased
impurity scattering, indicating that a greater amount of lattice damage is being repaired with each successive increase in
annealing temperature. These results provide suitable annealing conditions for Si-implanted Al
x
Ga1−x
N-based devices with an Al mole fraction from 11% to 51%. 相似文献
11.
D. Y. C. Lie J. H. Song F. Eisen M. A. Nicolet N. D. Theodore 《Journal of Electronic Materials》1996,25(1):87-92
A metastable Ge0.12Si0.88 layer 265 nm thick was deposited pseudomorphically on a Si(100) substrate and then implanted with 100 keV phosphorus ions
at room temperature for doses of 5 × 1013/cm2 to 1.5 × 1015/cm2. The ions stop within the epilayer (projected range ∼125 nm). MeV4He backscattering/channeling spectrometry, transmission electron microscopy, and double-crystal x-ray diffractometry were
used to characterize the damage and strain in the films. The samples were subsequently annealed in high vacuum from 400-800°C
for 30 min at each temperature. For the nonamorphized samples (doses of 5 and 10 × 1013/cm2), most of the implantation-induced damage and strain disappear after annealing at 400-550°C, but the implanted P ions activate
poorly. After annealing at 700-800°C, near complete activation is achieved but the strain relaxes. For the amorphized samples
(dose of 1.5 × 1015/cm2), the amorphous GeSi regrows by solid-phase epitaxy and the dopants are ∼100% activated after annealing at 550°C, but the
regrown GeSi relaxes with a high density of dislocations. The strain relaxes more extensively upon annealing in an implanted
sample than in a nonimplanted one, other conditions being equal. This effect is more pronounced at higher ion doses, probably
due to the increased amount of damage introduced at high doses.
On leave from Yonsei University, Seoul 120-749, Korea 相似文献
12.
B. A. Andreev N. A. Sobolev Yu. A. Nikolaev D. I. Kuritsin M. I. Makovijchuk E. O. Parshin 《Semiconductors》1999,33(4):407-409
In this paper the photoluminescence (PL) of holmium-doped silicon is discussed. The silicon was first implanted with holmium
ions at energies of 1–2 MeV and doses of 1×1013–3×1014 cm−2, and then annealed at temperatures of 620–900 °C for 0.5–1 h. In order to increase the concentration of electrically and
optically active centers, the silicon was implanted a second time with oxygen ions at energies of 0.14–0.29 MeV and doses
of 1×1014–3×1015 cm−2. Several photoluminescence lines, which are attributable to the transitions of electrons from the first excited state of
the Ho3+ ion (5
I
7) to the ground state (5
I
8), were observed. The amplitudes of the most intense lines, which correspond to transitions at frequencies 5119 and 5103 cm−1, decreased by more than an order of magnitude in the temperature range 4.2−78 K. The PL intensity of the holmium ions increased
with increasing concentrations of the implanted rare-earth ions and oxygen.
Fiz. Tekh. Poluprovodn. 33, 420–422 (April 1999) 相似文献
13.
Measurement of minority carrier lifetime in n-type MBE HgCdTe and its dependence on annealing 总被引:1,自引:0,他引:1
D. D. Edwall R. E. DeWames W. V. McLevige J. G. Pasko J. M. Arias 《Journal of Electronic Materials》1998,27(6):698-702
Results are presented for minority carrier lifetime in n-type molecular beam epitaxy Hg1−xCdxTe with x ranging from 0.2 to 0.6. It was found that the lifetime was unintentionally degraded by post-growth annealing under
Hg saturated conditions in a H2 atmosphere that was both time and temperature dependent. This effect was minimal or non-existent for x∼0.2 material, but
very strong for x ≥ 0.3. Hydrogen was identified as responsible for this degradation. Identical annealing in a He atmosphere
avoids this degradation and results in neartheoretical lifetime values for carrier concentrations as low 1 × 1015 cm−3 in ≥0.3 material. Modeling was carried out for x∼0.2 and x∼0.4 material that shows the extent to which lifetime is reduced
by Shockley-Real-Hall recombination for carrier concentrations below 1 × 1015 cm−3, as well as for layers annealed in H2. It appears that annealing in H2 results in a deep recombination center in wider bandgap HgCdTe that lowers the lifetime without affecting the majority carrier
concentration and mobility. 相似文献
14.
Mengkai Li Zhuo Wang Changlong Liu Junqi Liao Yanyan Shen Lili Zhang Bing Yuan 《Journal of Electronic Materials》2009,38(9):1990-1994
n-Type Si(100) wafers with a thermally grown Si3N4 layer (∼170 nm) were sequentially implanted with 160 keV He ions at a dose of 5 × 1016 cm−2 and 110 keV H ions at a dose of 1 × 1016 cm−2. Depending on the annealing temperature, surface exfoliations of two layers were observed by optical microscopy and atomic
force microscopy. The first layer exfoliation was found to correspond to the top Si3N4 layer, which was produced at lower annealing temperatures. The other was ascribed to the implanted Si layer, which was formed
at higher temperatures. The possible exfoliation processes are tentatively discussed, and potential applications of such phenomena
are also suggested. 相似文献
15.
Rapid thermal annealing (RTA) technology offers potential advantages for GaAs MESFET device technology such as reducing dopant
diffusion and minimizing the redistribution of background impurities. LEC semi-insulating GaAs substrates were implanted with
Si at energies from 100 to 400 keV to doses from 1 × 1012 to 1 × 1014/cm2. The wafers were encapsulated with Si3N4 and then annealed at temperatures from 850-1000° C in a commercial RTA system. Wafers were also annealed using a conventional
furnace cycle at 850° C to provide a comparison with the RTA wafers. These implanted layers were evaluated using capacitance-voltage
and Hall effect measurements. In addition, FET’s were fabricated using selective implants that were annealed with either RTA
or furnace cycles. The effects of anneal temperature and anneal time were determined. For a dose of 4 × 1012/cm2 at 150 keV with anneal times of 5 seconds at 850, 900, 950 and 1000° C the activation steadily increased in the peak of the
implant with overlapping profiles in the tail of the profiles, showing that no significant diffusion occurs. In addition,
the same activation could be obtained by adjusting the anneal times. A plot of the equivalent anneal times versus 1/T gives
an activation energy of 2.3 eV. At a higher dose of 3 × 1013 an activation energy of 1.7 eV was obtained. For a dose of 4 × 1012 at 150 keV both the RTA and furnace annealing give similar activations with mobilities between 4700 and 5000 cm2/V-s. Mobilities decrease to 4000 at a dose of 1 × 1013 and to 2500 cm2/V-s at 1 × 1014/cm2. At doses above 1 × 1013 the RTA cycles gave better activation than furnace annealed wafers. The MESFET parameters for both RTA and furnace annealed
wafers were nearly identical. The average gain and noise figure at 8 GHz were 7.5 and 2.0, respectively, for packaged die
from either RTA or furnace annealed materials. 相似文献
16.
Surface roughening in ion implanted 4H-silicon carbide 总被引:1,自引:0,他引:1
M. A. Capano S. Ryu J. A. Cooper Jr. M. R. Melloch K. Rottner S. Karlsson N. Nordell A. Powell D. E. Walker Jr. 《Journal of Electronic Materials》1999,28(3):214-218
Silicon carbide (SiC) devices have the potential to yield new components with functional capabilities that far exceed components
based on silicon devices. Selective doping of SiC by ion implantation is an important fabrication technology that must be
completely understood if SiC devices are to achieve their potential. One major problem with ion implantation into SiC is the
surface roughening that results from annealing SiC at the high temperatures which are needed to activate implanted acceptor
ions, boron or aluminum. This paper examines the causes and possible solutions to surface roughening of implanted and annealed
4H-SiC. Samples consisting of n-type epilayers (5 × 1015 cm−3, 4 μm thick) on 4H-SiC substrates were implanted with B or Al to a total dose of 4 × 1014 cm−2 or 2 × 1015 cm−2, respectively. Roughness measurements were made using atomic force microscopy. From the variation of root mean square (rms)
roughness with annealing temperature, apparent activation energies for roughening following implantation with Al and B were
1.1 and 2.2 eV, respectively, when annealed in argon. Time-dependent activation and surface morphology analyses show a sublinear
dependence of implant activation on time; activation percentages after a 5 min anneal following boron implantation are about
a factor of two less than after a 40 min anneal. The rms surface roughness remained relatively constant with time for anneals
in argon at 1750°C. Roughness values at this temperature were approximately 8.0 nm. Annealing experiments performed in different
ambients demonstrated the benefits of using silane to maintain good surface morphology. Roughnesses were 1.0 nm (rms) when
boron or aluminum implants were annealed in silane at 1700°C, but were about 8 and 11 nm for B and Al, respectively, when
annealed in argon at the same temperature. 相似文献
17.
Ruey-Shing Huang Chin-Hsiung Cheng J.C. Liu M.K. Lee C.T. Chen 《Solid-state electronics》1983,26(7):657-665
The electrical conduction properties of ion implanted polycrystalline silicon films have been studied. The polysilicon films were deposited by pyrolysis of silane at 647°C in LPCVD system onto oxide-coated silicon wafers to a thickness of 0.6 μm. Dopants were itroducd by implanting with boron or phosphorus ions, accelerated to 145 keV; doses ranged from 1 × 1012 cm?2 to 1 × 1015 cm?2. Film resistivities spanning 8 orders of magnitude were obtained using this doping range. Current-voltage characteristics of polysilicon resistors were measured at temperatures ranging from 24 to 140°C. The associated barrier heights and activation energies were derived. The grain-boundary trapping states density was estimated to be 5 × 1012 cm?2. We found that both dopant atom segregation and carrier trapping at the grain boundaries play important roles in polysilicon electrical conduction properties. However, within the dose range studies, the dopant atom segragation is most detrimental to the film conductivity for doses < 1 × 1013 cm?2; as the dose is increased, carrier trapping effects become more pronounced for doses up to 5 × 1014 cm?2. For doses ? 5 × 1014 cm?2, conduction due to carriers tunneling through the potential barriers at grain boundaries has to be considered. 相似文献
18.
N. Inoue A. Itoh T. Kimoto H. Matsunami T. Nakata M. Inoue 《Journal of Electronic Materials》1997,26(3):165-171
N+ implantation into p-type a-SiC (6H-SiC, 4H-SiC) epilayers at elevated temperatures was investigated and compared with implantation
at room temperature (RT). When the implant dose exceeded 4 × 1015 cm−2, a complete amorphous layer was formed in RT implantation and severe damage remained even after post implantation annealing
at 1500°C. By employing hot implantation at 500~800°C, the formation of a complete amorphous layer was suppressed and the
residual damage after annealing was significantly reduced. For implant doses higher than 1015 cm−2, the sheet resistance of implanted layers was much reduced by hot implantation. The lowest sheet resistance of 542Ω/ was
obtained by implantation at 500 ~ 800°C with a 4 × 1015 cm−2 dose. Characterization of n+-p junctions fabricated by N+ implantation into p-type epilayers was carried out in detail. The net doping concentration in the region close to the junction
showed a linearly graded profile. The forward current was clearly divided into two components of diffusion and recombination.
A high breakdown voltage of 615 ∼ 810V, that is almost an ideal value, was obtained, even if the implant dose exceeded 1015 cm−2. By employing hot implantation at 800°C, the reverse leakage current was significantly reduced. 相似文献
19.
Jakapan Chantana Daisuke Hironiwa Taichi Watanabe Seiki Teraji Takashi Minemoto 《Progress in Photovoltaics: Research and Applications》2016,24(7):990-1000
Cu(In,Ga)Se2 (CIGS) films on soda‐lime glass and stainless steel (SUS) substrates with several [Ga]/([Ga] + [In]), GGI, and Fe concentrations are fabricated by so‐called “multi‐layer precursor method”. From optical deep‐level transient spectroscopy, deep‐level defect located at 0.8 eV from valence band maximum (EV) is observed. This defect becomes recombination center when GGI is over 0.4, thereby decreasing cell performances. Fe‐related deep‐level defect is moreover detected in CIGS film on SUS substrate situated at 0.45 eV from EV. Its density is consistent with Fe concentration in CIGS films. According to SCAPS simulation and experimental results, Fe concentration of above threshold (1.0 × 1016 atom/cm3) decreases carrier lifetime and carrier density and has more harmful influence on cell performances with GGI of above 0.4. On the other hand, Fe concentration of below threshold (1.0 × 1016 atom/cm3) has no detrimental impact on cell performances. Namely, conversion efficiency (η) is slightly changed by below 2%. CIGS solar cell on SUS substrate with η of 17.5% is fabricated by decreasing Fe concentration to approximately 5.2 × 1016 atom/cm3 although higher than the threshold value. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
20.
James A. Fellows Y. K. Yeo Mee-Yi Ryu R. L. Hengehold 《Journal of Electronic Materials》2005,34(8):1157-1164
Comprehensive and systematic electrical and optical activation studies of Si-implanted GaN were made as a function of ion dose and anneal temperature. Silicon ions were implanted at 200 keV with doses ranging from 1×1013 cm?2 to 5×1015 cm?2 at room temperature. The samples were proximity-cap annealed from 1050°C to 1350°C with a 500-Å-thick AlN cap in a nitrogen environment. The optimum anneal temperature for high dose implanted samples is approximately 1350°C, exhibiting nearly 100% electrical activation efficiency. For low dose (≤5×1014 cm?2) samples, the electrical activation efficiencies continue to increase with an anneal temperature through 1350°C. Consistent with the electrical results, the photoluminescence (PL) measurements show excellent implantation damage recovery after annealing the samples at 1350°C for 20 sec, exhibiting a sharp neutral-donor-bound exciton peak along with a sharp donor-acceptor pair peak. The mobilities increase with anneal temperature, and the highest mobility obtained is 250 cm2/Vs. The results also indicate that the AlN cap protected the implanted GaN layer during high-temperature annealing without creating significant anneal-induced damage. 相似文献