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1.
Mulpuri V. Rao Sadanand M. Gulwadi Phillip E. Thompson Ayub Fathimulla Olaleye A. Aina 《Journal of Electronic Materials》1989,18(2):131-136
Halogen lamp rapid thermal annealing was used to activate 100 keV Si and 50 keV Be implants in In0.53Ga0.47As for doses ranging between 5 × 1012−4 × 1014 cm−2. Anneals were performed at different temperatures and time durations. Close to one hundred percent activation was obtained
for the 4.1 × 1013 cm−2 Si-implant, using an 850° C/5 s anneal. Si in-diffusion was not observed for the rapid thermal annealing temperatures and
times used in this study. For the 5 × 1013 cm−2 Be-implant, a maximum activation of 56% was measured. Be-implant depth profiles matched closely with gaussian profiles predicted
by LSS theory for the 800° C/5 s anneals. Peak carrier concentrations of 1.7 × 1019 and 4 × 1018 cm−3 were achieved for the 4 × 1014 cm−2 Si and Be implants, respectively. For comparison, furnace anneals were also performed for all doses. 相似文献
2.
To obtain highly conductive buried layers in InP:Fe, MeV energy Si, S, and Si/ Simplantations are performed at 200°C. The
silicon and sulfer implants gave 85 and 100 percent activation, respectively, for a fluence of 8 × 1014 cm−2. The Si/S co-implantation also gave almost 100 percent donor activation for a fluence of 8 × 1014 cm−2 of each species. An improved silicon donor activation is observed in the Si/S co-implanted material compared to the material
implanted with silicon alone. The peak carrier concentration achieved for the Si/S co-implant is 2 × 1019 cm3. The lattice damage on the surface side of the profile is effectively removed after rapid thermal annealing. Multiple-energy
silicon and sulfur implantations are performed to obtain thick and buried n+ layers needed for microwave devices and also hyper-abrupt profiles needed for varactor diodes. 相似文献
3.
Chemical and damage effects are used to explain the influence of complementary species on the activation of co-implanted InP.
Recently Raoet al. have shown that the damage is the effective mechanism of enhancing activation efficiency and preventing in-diffusion in the
P/Be and Ar/Be co-implanted InP. We have confirmed the results and further examined the role of the complementary species
by varying their doses. Activation efficiencies as high as 75% and 69.5% were observed in the P/Be and Ar/Be co-implantation,
respectively, which can be compared with 31.7% activation in the Be single implantation. Both activation efficiency and in-diffusion
decreased as doses of P and Ar increased, that is, as the amount of damage increased. P/Be had always higher activation efficiency
than that of Ar/Be when the doses of co-implants are equal. The ratio of the difference in the two activation efficiencies
to that of P/Be was the largest at 1014 cm−2 of co-implant dose. This behavior was attributed to the chemical effect of the co-implanted P. Photoluminescence results
near the band edge showed that the intensity of the main peaks of Be single implantation decreased with increasing P and Ar
doses. 相似文献
4.
Jayadev Vellanki Ravi K. Nadella Mulpuri V. Rao Harry B. Dietrich David S. Simons Peter H. Chi 《Journal of Electronic Materials》1993,22(5):559-566
Room temperature and elevated temperature sulfur implants were performed into semi-insulating GaAs and InP at variable energies
and fluences. The implantations were performed in the energy range 1–16 MeV. Range statistics of sulfur in InP and GaAs were
calculated from the secondary ion mass spectrometry atomic concentration depth profiles and were compared with TRIM92 values.
Slight in-diffusion of sulfur was observed in both InP and GaAs at higher annealing temperatures for room temperature implants.
Little or no redistribution of sulfur was observed for elevated temperature implants. Elevated temperature implants showed
higher activations and higher mobilities compared to room temperature implants in both GaAs and InP after annealing. Higher
peak electron concentrations were observed in sulfur-implanted InP (n ≈ 1 × 1019 cm−3) compared to GaAs (n ≈ 2 × 1018 cm−3). The doping profile for a buried n+ layer (n ≈ 3.5 × 1018 cm−3) of a positive-intrinsic-negative diode in GaAs was produced by using Si/S coimplantation. 相似文献
5.
Si- and Mg-ions with energies of 180 keV have been implanted into semi-insulating InP substrates and low doped n- and p-type
GalnAs epitaxial layers (3 · l016cm−3). Sheet resistances and doping profiles are analyzed and compared with LSS theory. Post-implantation annealing is studied
with respect to encapsulation, time and temperature. We have tested as new encapsulation techniques for InP the simple proximity
cap annealing and for GalnAs the As-doped spun-on SiO2. Proximity cap annealing yields decomposition-free surfaces when using a recessed capsubstrate. At annealing temperatures
of around 800 °C less activation is obtained than with conventional PSG annealing and a surface accumulation of charge-carriers
is established. A time limit of around 3 min is found for Si- and Mg-implanted InP, beyond which the sheet resistance no longer
decreases and the doping saturates. For Si in InP, short-time annealing yields to a 68 % activation of carriers, not significantly
higher than with conventional long-time annealing. In the case of Si in GalnAs, however, short-time annealing is much more
effective. A 100 % activation is obtained for a dose of 2.1014 cm−2, while only 7 % is found for long annealing. Even at such a high dose of 1. 1016cm−2 we have achieved about an order of magnitude higher activation with short annealing than with long annealing.
Most information contained in this paper was presented at the 1984 Electron Materials Conference as paper L-l. 相似文献
6.
R. D. Dupuis C. J. Eiting P. A. Grudowski H. Hsia Z. Tang D. Becher H. Kuo G. E. Stillman M. Feng 《Journal of Electronic Materials》1999,28(3):319-324
Ion implantation into III–V nitride materials is animportant technology for high-power and high-temperature digital and monolithic
microwave integrated circuits. We report the results of the electrical, optical, and surface morphology of Si ion-implanted
GaN films using furnace annealing. We demonstrate high sheet-carrier densities for relatively low-dose (natoms=5×1014 cm−2) Si implants into AlN/GaN/sapphire heteroepitaxial films. The samples that were annealed at 1150°C in N2 for 5 min exhibited a smooth surface morphology and a sheet electron concentration ns ∼9.0×1013 cm−2, corresponding to an estimated 19% electrical activation and a 38% Si donor activation in GaN films grown on sapphire substrates.
Variable-temperature Hall-effect measurem entsindicate a Si donor ionization energy ∼15 meV. 相似文献
7.
Donor ion-implantation doping into SiC 总被引:1,自引:0,他引:1
Mulpuri V. Rao J. Tucker O. W. Holland N. Papanicolaou P. H. Chi J. W. Kretchmer M. Ghezzo 《Journal of Electronic Materials》1999,28(3):334-340
In this paper, dopant electrical activation and dopant thermal stability results of As and Sb-implanted 6H-SiC epitaxial layers
and N ion implantations into bulk semi-insulating (SI) 4H-SiC are presented. In addition, empirical formulas for the first
four statistical moments (range, straggle, skewness, and kurtosis) of the implant depth distributions of N and P ion implants
are developed in the energy range of 50 keV to 4 MeV. The nitrogen ion-implantations in SI 4H-SiC yield an acceptable (27%)
room-temperature electrical activation (ratio of measured sheet carrier concentration at room-temperature to the implant dose)
for N concentrations of 2×1019 cm−3. The As and Sb implants out-diffuse during annealing and yield low (<20%) room-temperature electrical activation for implant
concentrations of 1019 cm−3. The N and P implant depth distributions in SiC can be simulated using the Pearson IV distribution function and the range
statistics provided by the empirical formulas. 相似文献
8.
A study of the electrical characteristics of InP implanted with C, Si, Ge and Sn demonstrates that all of these column IV elements are donors, although the net electrical activation achieved with the light ion C was only about 5%. Samples implanted at temperatures of 150–200°C generally had lower sheet resistivities, higher mobilities and except for high doses, higher sheet carrier concentrations than those done at room temperatures. Implants at 150–200°C with 1 × 1014cm?2 of the heavier ions, Si, Ge or Sn, resulted in layers with sheet carrier concentrations of 7.8 × 1013, 5.6 × 1013 and 4.7 × 1013cm?2, respectively. Carrier concentration profiles of samples implanted at 200°C with 1 × 1014cm?2 of Si agreed reasonably well with LSS theory. Higher doses gave rise to substantial diffusion of the implanted Si, whereas room temperature implants showed poor activation near the surface. 相似文献
9.
C. Jasper R. Morton S. S. Lau T. E. Haynes J. W. Mayer K. S. Jones 《Journal of Electronic Materials》1996,25(1):107-111
For implantation of silicon dopant into gallium arsenide, sheet resistance and damage increase as the ion dose rate increases
in the high-dose regime (>5.0 × 1013 cm−2). But, in the low-dose regime (<5.0 × 1012 cm−2), although damage still increases with dose rate, the sheet resistance decreases. This qualitative difference implies that
there must be a crossover point between the low- and high-dose regimes in the effect of damage and defect formation on dopant
activation. This paper describes experiments in which damage and silicon dose were independently varied through the crossover
point. Thermal wave, ion channeling, Hall effect measurements, and transmission electron microscopy were used to characterize
structural and electrical changes that occur near the crossover. In GaAs implanted with silicon (29Si+) at doses between 3 × 1012 and 6 × 1013cm−2, it is shown that electrical activation for low dose rates first begins to exceed that for high dose rates at a dose of 2
× 1013 cm−2. Rapid growth of Type I dislocations also begins near this same dose, suggesting that there may be a link between defect
formation and the crossover to negative dose-rate effects in the high-dose regime. 相似文献
10.
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
11.
The electrical properties of C-implanted <100> GaAs have been studied following rapid thermal annealing at temperatures in
the range from 750 to 950°C. This includes dopant profiling using differential Hall measurements. The maximum p-type activation
efficiency was found to be a function of C-dose and annealing temperature, with the optimum annealing temperature varying
from 900°C for C doses of 5 × 1013 cm−2 to 800°C for doses ≥5 × 1014cm−2. For low dose implants, the net p-type activation efficiency was as high as 75%; while for the highest dose implants, it
dropped to as low as 0.5%. Moreover, for these high-dose samples, 5 × 1015 cm−2, the activation efficiency was found to decrease with increasing annealing temperature, for temperatures above ∼800°C, and
the net hole concentration fell below that of samples implanted to lower doses. This issue is discussed in terms of the amphoteric
doping behavior of C in GaAs. Hole mobilities showed little dependence on annealing temperature but decreased with increasing
implant dose, ranging from ∼100 cm2/V·s for low dose implants, to ∼65 cm2/V·s for high dose samples. These mobility values are the same or higher than those for Be-, Zn-, or Cd-implanted GaAs. 相似文献
12.
Characterization of phosphorus implantation in 4H-SiC 总被引:3,自引:0,他引:3
V. Khemka R. Patel N. Ramungul T. P. Chow M. Ghezzo J. Kretchmer 《Journal of Electronic Materials》1999,28(3):167-174
We report the characterization of phosphorus implantation in 4H-SiC. The implanted layers are characterized by analytical
techniques (secondary ion mass spectrometry, transmission electron microscopy) as well as electrical and a sheet resistance
value as low as 160 Ω/□ has been measured. We have also studied the effect of annealing time and temperature on activation
of phosphorus implants. It has been shown to possible to obtain low sheet resistance (∼260 Ω/□) by annealing at a temperature
as low as 1200°C. High-dose (∼ 4 × 1015 cm−2) implants are found to have a higher sheet resistance than that on lower dose implants which is attributed to the near-surface
depletion of the dopant during high temperature anneal. Different implantation dosages were utilized for the experiments and
subsequently junction rectifiers were fabricated. Forward characteristics of these diodes are observed to obey a generalized
Sah-Noyce-Shockly multiple level recombination model with four shallow levels and one deep level. 相似文献
13.
Thin films of InP were deposited on single crystals and thin films of CdS by the planar reactive deposition technique. Good
local epitaxy was observed on single crystals of CdS as well as InP and GaAs. The electrical evaluation of unintentionally
doped films on semi-insulating InP substrates show them to be n-type with room temperature electron concentrations ranging
from 5 × 1016 cm−3 to 5 × 1017 cm−3 and mobilities up to 1350 cm2/Vsec. For films intentionally doped with Mn and Be, p-type films were obtained. For Mn doping (deep acceptor level), room
temperature mobilities as high as 140 cm2/Vsec and free carrier concentrations as low as 5 × 1016 cm−3 (with dopant level of 3 × 1018 cm−3) were obtained. For Bedoped films, free carrier concentrations of about 5 × 1018 cm−3 and mobilities of 20 cm2/Vsec were found. Scanning electron microscope and microprobe pictures show appreciable interdiffusion between the InP/CdS
thin-film pair for InP deposited at 450°C. The loss of Cd from the CdS and the presence of an indium-cadmium-sulfur phase
at the InP/CdS interface were observed. Interdiffusion is alleviated for InP deposition at lower temperatures.
Supported in part by ERDA and AFOSR. 相似文献
14.
Tsunenobu Kimoto Akira Itoh Hiroyuki Matsunami Toshitake Nakata Masanori Watanabe 《Journal of Electronic Materials》1995,24(4):235-240
Ion implantation of nitrogen (N) into p-type 6H-SiC {0001} epilayers was investigated as a function of implant dose. Lattice
damage induced by implantation was characterized by Rutherford backscattering spectroscopy and Raman scattering. The damage
severely increased when the implant dose exceeds 1 x 1015 cm-2, and amorphous layers were formed at doses higher than 4 x 1015 cm-2. By high-temperature annealing at 1500°C, relatively high electrical activation ratios (≈50%) can be obtained in the case
of low-dose implantation (<1 x 1015cm−2). However, the electrical activation showed sharp decrease with increasing implant dose, which may be caused by the residual
damage in implanted layers. 相似文献
15.
The surface recombination of GaAs which has a heavily doped surface layer formed by Si implantation and subsequent annealing
has been investigated using the noncontact laser/microwave evaluation method. The experimental results of the samples implanted
with doses ranging from 1.0 × 1011 to 3.9 × 1012 cm−2 at an energy of 100 keV indicate that the effective surface recombination velocity decreases with dosage because of the heavily
doped layer formed after the annealing. On the other hand, the results of the samples implanted with a dose of 3.9 × 1012 cnr−2 at energies raging from 50 to 180 keV indicate that the effective surface recombination velocity increases with energy. This
is mainly due to the decrease in the peak carrier concentration in the heavily doped layer. 相似文献
16.
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
17.
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
18.
Mulpuri V. Rao R. Sachidananda Babu Alok K. Berry Harry B. Dietrich Nick Bottka 《Journal of Electronic Materials》1990,19(8):789-794
200 keV Si implantations were performed in the dose range of 5 × 1012 − 1 × 1014 cm−2 in GaAs grown on Si. For comparison implants were also performed in GaAs layers grown on GaAs substrates. Implanted layers
were annealed by both furnace and halogen lamp rapid thermal anneals. Significantly lower donor activations were observed
in GaAs layers grown on Si substrates than in the layers grown on GaAs substrates. Extremely low dopant activations were obtained
for Be implants in GaAs grown on Si. Photoluminescence and photoreflectance measurements were also performed on the implanted
material. 相似文献
19.
Boron implanted into n-type Si at 1015 cm−2 dose and energies from 500 eV to 1 keV was activated by annealing in nominally pure N2 and in N2 with small admixtures of O2. Effective process times and temperatures were derived by thermal activation analysis of various heating cycles. The lowest
thermal budgets used “spike anneals” with heating rates up to 150°C/sec, cooling rates up to 80°C/sec, and minimal dwell time
at the maximum temperature. Dopant activation was determined by sheet electrical transport measurements. Surface oxidation
was characterized by film thickness ellipsometry. P-n junction depths were inferred from analysis of sheet electrical transport
measurements and secondary ion mass spectroscopy profiles. Boron activation increases with boron diffusion from the implanted
region. Electrical activation has a thermal activation energy near 5 eV, while boron diffusion has an activation energy near
4 eV. Surface oxide can retard boron diffusion into the ambient for high-temperature anneals. 相似文献
20.
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