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1.
Mulpuri V. Rao Sadanand M. Gulwadi Savitri Mulpuri David S. Simons Peter H. Chi C. Caneau W-P. Hong O. W. Holland Harry B. Dietrich 《Journal of Electronic Materials》1992,21(9):923-928
Elevated temperature (200° C) single- and multiple-energy Co implants inn-type InP, Co and Fe implants in n-type In0.53Ga0.47As, and Ti implants inp-type In0.53Ga0.47As were performed. For elevated temperature, single-energy Co and Fe implants, no satellite peaks at various locations like
0.8R
P, RP
+ ΔRP, and 2R
P
R
P is the projected range and ΔR
P the straggle of the implant) are observed, in contrast to the case of room temperature implants. However, the outdiffusion
of the implant is as severe as that in room temperature implantation for high temperature anneals. Indiffusion of the implant
also occurs, but it is not as severe as the outdiffusion. High temperature annealing of Ti-implanted material results in a
slight indiffusion of Ti, with minimal redistribution or outdiffusion. For all elevated temperature implants, the lattice
quality of the annealed material is close to that of the virgin unimplanted material. For all ion species used in this study,
resistivities close to the intrinsic limit are obtained in the implanted and annealed materials. 相似文献
2.
Shih-Yuan Lin Ying-Chung Chen Chih-Ming Wang Kuo-Sheng Kao Chih-Yuan Chan 《Journal of Electronic Materials》2009,38(3):453-459
Calcium copper titanium oxide (CaCu3Ti4O12, abbreviated to CCTO) films were deposited on Pt/Ti/SiO2/Si substrates at room temperature (RT) by radiofrequency magnetron sputtering. As-deposited CCTO films were treated by rapid
thermal annealing (RTA) at various temperatures and in various atmospheres. X-ray diffraction patterns and scanning electron
microscope (SEM) images demonstrated that the crystalline structures and surface morphologies of CCTO thin films were sensitive
to the annealing temperature and ambient atmosphere. Polycrystalline CCTO films could be obtained when the annealing temperature
was 700°C in air, and the grain size increased signifi- cantly with annealing in O2. The 0.8-μm CCTO thin film that was deposited at RT for 2 h and then annealed at 700°C in O2 exhibited a high dielectric constant (ε′) of 410, a dielectric loss (tan δ) of 0.17 (at 10 kHz), and a leakage current density (J) of 1.28 × 10−5 A/cm2 (at 25 kV/cm). 相似文献
3.
The annealing temperature (25–700°C) dependence of Schottky contact characteristics on n-GaN using a TiB2/Ti/Au metallization scheme deposited by sputtering is reported. The Schottky barrier height increased from 0.65 to 0.68 eV
as the anneal temperature was varied from 25°C to 350°C and decreased to 0.55 eV after annealing at 700°C. The barrier height
showed no measurable dependence on measurement temperature up to 150°C. The elemental profile obtained from samples annealed
at 350°C showed limited Ti diffusion from the elemental Ti layer into the gold layer. Annealing at 700°C produced significant
out-diffusion of this layer, while the TiB2 layer retained its stability. These contacts show promise for applications requiring good thermal stability, such as power
amplifiers, but much more work is needed to establish their long-term reliability. In addition, TiB2 has a strong propensity for oxidation, and it is imperative that overlayers such as Au be deposited in the same deposition
chamber. 相似文献
4.
K. L. Fry C. P. Kuo C. A. Larsen R. M. Cohen G. B. Stringfellow A. Melas 《Journal of Electronic Materials》1986,15(2):91-96
We report the organometallic vapor phase epitaxial (OMVPE) growth of InP and Ga0.47In0.53As using a new organometallic indium source, ethyldimethylindium (EDMIn), rather than the traditional sources triethylindium
(TEIn) or trimethylindium (TMIn). EDMIn is a liquid at room temperature and its vapor pressure at 17° C was found to be 0.85
Torr using thermal decomposition experiments. The growth results using EDMIn were compared to those using TMIn in the same
atmospheric pressure reactor. For InP, use of EDMIn resulted in a high growth efficiency of 1.3 × 104 μm/ mole, which was independent of the growth temperature and comparable to the growth efficiency obtained with TMIn. The
high growth efficiency is consistent with the observation of no visible parasitic gas phase reactions upstream of the substrate.
The 4K photoluminescence (PL) spectra consist of a peak due to bound excitons and an impurity related peak 38 meV lower in
energy. This impurity peak is ascribed to conduction band to acceptor transitions from carbon, due to the decreasing relative
intensity of this peak with increasing V/III ratio. The relative intensity of the C impurity peak decreases by five times
when the growth temperature is increased from 575 to 675° C, with a corresponding increase in the room temperature electron
mobility from 725 to 3875 cm2/ Vs. For GalnAs lattice-matched to InP, use of EDMIn also resulted in a temperatureindependent high growth efficiency of
1.0 x 104 μm/mole, indicating negligible parasitic reactions with AsH3. The In distribution coefficient was nearly constant at a value of 0.9, however the run to run composition variation was
slightly higher for EDMIn than for TMIn. The 4K PL showed donor-acceptor pair transitions due to C and Zn. The C impurity
peak intensity decreased dramatically with increasing growth temperature, accompanied by an increase in the room temperature
electron mobility to 5200 cm2/Vs. Overall, the growth of both InP and GalnAs using EDMIn was qualitatively similar to that using TMIn, although the room
temperature electron mobilities were lower for the new source than for our highest purity bottle of TMIn. 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.
Rapid isothermal annealing (RIA) was performed on 0.5-16-MeV Si +, 1-MeV Be+, and 150-keV Ge+ implanted InP:Fe and 380-keV Fe+ implanted InGaAs. Annealings were performed in the temperature range 800-925°C using an InP proximity wafer in addition to the Si3N4 dielectric cap. Dopant activations close to 100% were obtained for 3×1014 cm-2 Si+ and 2×1014 cm-2 Be+ implants in InP:Fe. For the elevated temperature (200°C) 1×1014 cm-2 Ge+ implant, a maximum of 50% activation was obtained. No redistribution of dopant was observed for Si and Ge implants due to annealing. However, redistribution of dopant was seen for Be and Fe implants due to annealing. Phosphorous coimplantation has helped to eliminate the Be in-diffusion problem in InP, but did not help to reduce Fe in-diffusion and redistribution in InGaAs. Using an RIA cycle with low temperature and short duration is the only solution to minimize Fe redistribution in InGaAs 相似文献
7.
We report the results of capacitance-voltage (C-V) and Deep Level Transient Spectroscopy (DLTS) measurements performed upon
a Ga0.47In0.53As/InP quantum well structure. At room temperature, a conduction-band offset ΔEc=(200±10)meV and charge densities σI=±(3±1)*1011 times the electronic charge per cm2 have been measured from C-V experiments. At lower temperature (T≤150K) we have observed an important decrease of the band-offset,
considerably larger than a pure thermal effect. We have shown that the explanation lies in the presence of a high concentration
of deep traps located at the well-barrier interfaces. Two species A and B have been detected through DLTS experiments with
activation energies EtA=90 meV and EtB=195 meV, respectively. The filling of these trap levels at low temperature lowers the band offset from 200 to 120 meV, owing
to band repulsion effects. 相似文献
8.
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
9.
The SiO2 film as an insulator in InP MOS structure was grown by mercury-sensitized photo induced chemical-vapor deposition (photo-CVD)
utilizing gaseous mixture of monosilane (SiH4) and nitrous oxide (N4O) under 253.7 nm ultraviolet light irradiation. The PHOTOX SiO2 film (i.e., SiO2 film prepared by photo-CVD system) deposited at 250° C has a refractive index of 1.46 and breakdown field strength of 7.0
MV/cm. The 1 MHz capacitance-voltage characteristics of the InP MOS diode was measured to study the interface state densities.
The minimum value is 1.2 × 1011 cm−2eV−1 for the sample prepared at a substrate temperature of 250° C. 相似文献
10.
W.T. Lim P.W. Sadik D.P. Norton B.P. Gila S.J. Pearton I.I. Kravchenko F. Ren 《Journal of Electronic Materials》2008,37(2):161-166
The use of Ir diffusion barriers in Ni/Au-based Ohmic contacts to p-type CuCrO2 layers was investigated. A specific contact resistance of ~5 × 10−4 Ω cm2 was achieved after annealing at 500°C for the Ir-containing contacts, and the contacts were rectifying for lower anneal temperatures.
In this case, the contact resistance was basically independent of the measurement temperature, indicating that tunneling is
the dominant transport mechanism in the contacts. The morphology for the Ir-containing contacts was still smooth at 500°C
although Auger electron spectroscopy depth profiling showed that some of the nickel had diffused to the surface and had oxidized.
Contacts annealed at 800°C showed that some copper and most of the nickel had diffused to the surface and oxidized. The presence
of the Ir diffusion barrier does increase the thermal stability of the contacts by ∼200°C compared to conventional Ni/Au contacts.
By contrast, the use of other materials such as TaN, ZrN, and W2B5 as the diffusion barrier led to poorer thermal stability, with the contact resistance increasing sharply above 400°C. 相似文献
11.
S. A. Stockman A. W. Hanson C. M. Colomb M. T. Fresina J. E. Baker G. E. Stillman 《Journal of Electronic Materials》1994,23(8):791-799
Factors which influence the alloy composition and doping level of CCl4-doped In0.53Ga04.7As grown at low temperatures (450°C < Tg < 560°C) by low-pressure metalorganic chemical vapor deposition (MOCVD) have been investigated. The composition is highly
dependent on substrate temperature due to the preferential etching of In from the surface during growth and the temperature-dependent
growth efficiency associated with the Ga source. The lower pyrolysis temperature of TEGa relative to TMGa allows the growth
of CCl4-doped InGaAs at lower growth temperatures than can be achieved using TMGa, and results in improved uniformity. High p-type
doping (p ∼ 7 × 1019 cm-8) has been achieved in C-doped InGaAs grown at T = 450°C. Secondary ion mass spectrometry analysis of a Cdoping spike in InGaAs
before and after annealing at ∼670°C suggests that the diffusivity of C is significantly lower than for Zn in InGaAs. The
hole mobilities and electron diffusion lengths in p+-InGaAs doped with C are also found to be comparable to those for Be and Zn-doped InGaAs, although it is also found that layers
which are highly passivated by hydrogen suffer a degradation in hole mobility. InP/InGaAs heterojunction bipolar transistors
(HBTs) with a C-doped base exhibit high-frequency performance (ft = 62 GHz, fmax=42 GHz) comparable to the best reported results for MOCVD-grown InP-based HBTs. These results demonstrate that in spite of
the drawbacks related to compositional nonuniformity and hydrogen passivation in CCl4-doped InGaAs grown by MOCVD, the use of C as a stable p-type dopant and as an alternative to Be and Zn in InP/ InGaAs HBTs
appears promising. 相似文献
12.
Yoon-Bong Hahn Jong-Wha Kim Chang-Joo Youn In-Sun Lee 《Journal of Electronic Materials》1997,26(12):1394-1400
Dielectric PbTiO3-thin films were prepared on p-Si(100) substrate by plasma enhanced metalorganic chemical vapor deposition using high purity
Ti(O-i-C3H7)4, Pb(tmhd)2, and oxygen. As-deposited films were post-treated by rapid thermal annealing method, and the effect of annealing was examined
under various conditions. The deposition process was controlled by mixed-control scheme at temperatures lower than 350°C,
but controlled by heterogeneous surface reaction at temperatures greater than 350°C. The as-deposited films showed PbO structure
at 350∼400°C, but (100) and (101) PbTiO3 orientations started to appear at 450°C. The deposition rate was increased with rf power due to the enhanced dissociation
of Ti and Pb precursors. It was found that the concentration of oxygen plays an important role in crystallization of PbTiO3 during the rapid thermal annealing. A linear relationship was obtained between the dielectric constant of PbTiO3 films and the annealing temperature. However, the surface roughness and leakage current density increased mainly due to the
defects caused by volatilization of lead and the interface layer formed during the high temperature annealing. 相似文献
13.
Kamal Tabatabaie-Alavi Ernesto H. Perea Clifton G. Fonstad 《Journal of Electronic Materials》1981,10(3):591-603
Data for nearly-equilibrium LPE growth at 626°C of InGaAs lattice-matched to the <100> face of InP are presented and the modeling
of phase equilibria in this system is discussed. Because the simple solution approximation, which is useful for modeling binary
(InP) and ternary (InGaAs) growth, is found to be unsatisfactory for the quaternary, a semi-empirical model suitable for determining
the phase equilibria for LPE growth of any lattice-matched composition over a wide temperature range is proposed. The model
is based on a simple scaling of data for lattice-matched growth at one liquidus temperature, 626°C, to other temperatures
using data for the two lattice-matching compositions, InP and InGaAs, for which the temperature dependencies can be calculated.
Using this ‘model’, melt compositions for growth with 600 < Tℓ < 660°C are calculated and compared with expermental results. The nearly-equilibrium growth technique is fully described
and empirical techniques for adjusting melt compositions to improve the degree of lattice-match are also given. 相似文献
14.
A. A. Iliadis J. K. Zahurak T. Neal W. T. Masselink 《Journal of Electronic Materials》1999,28(8):944-948
We have investigated the formation of source-drain AuGe/Au and Ni/AuGe/Ni/Au alloyed ohmic contacts to AlInAs/InGaAs/InP doped
channel MODFETs, and observed lateral diffusion of the contact system after the standard annealing procedure at the temperature
range of 185 to 400°C. Auger depth profiling of contacts annealed at 250°C, revealed that Au(Ge) diffused through the top
InGaAs and AlInAs layers into the active InGaAs layer, but had reduced penetration into the AlInAs buffer layer. This reduction
in diffusion along the depth axis at the AlInAs buffer layer boundary is believed to result in enhanced lateral diffusion
and the observed lateral encroachment of the contacts. Both Au and Ni containing contact systems showed similar behavior in
terms of lateral diffusion with encroachment extending between 0.25 and 0.5 μm at the periphery of the contacts for annealing
temperatures between 300 and 400°C. A controlled ramp-to-peak temperature annealing procedure is developed to suppress such
lateral diffusion effects. Low temperature annealing (250°C) using this procedure resulted in equally low contact resistance
values (∼0.1Θ-mm) and no lateral diffusion. It is concluded that in thin multilayered structures the modified annealing procedure
presented here, is necessary for optimal ohmic contact formation. 相似文献
15.
S. Tsukimoto K. Nitta T. Sakai M. Moriyama Masanori Murakami 《Journal of Electronic Materials》2004,33(5):460-466
In order to understand a mechanism of TiAl-based ohmic contact formation for p-type 4H-SiC, the electrical properties and
microstructures of Ti/Al and Ni/Ti/Al contacts, which provided the specific contact resistances of approximately 2×10−5 Ω-cm2 and 7×10−5 Ω-cm2 after annealing at 1000°C and 800°C, respectively, were investigated using x-ray diffraction (XRD) and high-resolution transmission
electron microscopy (HRTEM). Ternary Ti3SiC2 carbide layers were observed to grow on the SiC surfaces in both the Ti/Al and the Ni/Ti/Al contacts when the contacts yielded
low resistance. The Ti3SiC2 carbide layers with hexagonal structures had an epitaxial orientation relationship with the 4H-SiC substrates. The (0001)-oriented
terraces were observed periodically at the interfaces between the carbide layers and the SiC, and the terraces were atomically
flat. We believed the Ti3SiC2 carbide layers primarily reduced the high Schottky barrier height at the contact metal/p-SiC interface down to about 0.3
eV, and, thus, low contact resistances were obtained for p-type TiAl-based ohmic contacts. 相似文献
16.
The electrical characteristics of Pd/p-Si1-xGex Schottky contacts have been investigated. The Schottky contacts were formed by depositing Pd metal on substrates at room
temperature (RT = 300K) and at low temperature (LT = 77K). Post annealing was performed in nitrogen atmosphere at 450 and
550°C, respectively, to study the effect of silicide formation on contact characteristics. The current-voltage measurements
showed that the barrier height, ϕB, decreased with the increase of the gemanium composition. The contact postannealed at 550°C showed a current transport mechanism
obviously different from the as-deposited Schottky contacts. Nearly identical characteristics were observed for the low temperature
deposited contacts and the room temperature deposited contacts with 550°C post-annealing. They both showed thermionic emission
dominated transport mechanism. X-ray diffraction technique was used to characterize the effect of different temperature treatments
on the crystal structure. The full width at half maximum of Si1-xGex(400) phase decreased at low temperature deposited sample, while it increased at room temperature deposition. 相似文献
17.
Ohmic contacts have been fabricated on p-type 6H-SiC (1.3×1019 cm−3) using CrB2, W2B, and TiB2. The boride layers (∼100–200 nm) were sputter-deposited in a system with a base pressure of 3×10−7 Torr. Specific contact resistances were measured using the linear transmission line method, and the physical properties of
the contacts were examined using Rutherford backscattering spectrometry. All as-deposited contacts exhibited rectifying characteristics.
Ohmic behavior was observed following short anneals (2–10 min) at 1100°C and 5×10−7 Torr. Current-voltage characteristics were linear for CrB2 and W2B and quasi-linear for TiB2. The lowest values of the specific contact resistance (rc in Ω-cm2) measured at room temperature for CrB2 and W2B were 8.2×10−5 and 5.8×10−5, respectively. The specific contact resistance for TiB2 was not determined accurately. Longer anneals (30 min for W2B and 90 min for CrB2) reduced the room temperature values of rc to 6.1×10−5 for W2B and 1.9×10−5 for CrB2. Backscattering spectra revealed substantial concentrations of oxygen in all as-deposited boride films. The short anneal
cycle removed the oxygen in the CrB2 films and reduced the concentration substantially in the W2B films; however, annealing had no affect on the oxygen concentration in the TiB2 films. The CrB2/SiC interface remained stable during annealing; i.e., Si and carbon were not observed in the boride layers after annealing.
In contrast, W2B and TiB2 reacted with the SiC epilayers, and after annealing, Si and carbon were observed at the surface of each boride layer. 相似文献
18.
Y. He J. Ramdani N. A. El-Masry D. C. Look S. M. Bedair 《Journal of Electronic Materials》1993,22(12):1481-1485
Low-temperature (LT) growth of In0.47Ga0.53P was carried out in the temperature range from 200 to 260°C by gas source molecular beam epitaxy using solid Ga and In and
precracked PH3. The Hall measurements of the as-grown film showed a resistivity of ∼106 Ω-cm at room temperature whereas the annealed film (at 600°C for 1 h) had at least three orders of magnitude higher resistivity.
The Hall measurements, also, indicated activation energies of ∼0.5 and 0.8 eV for the asgrown and annealed samples, respectively.
Double-crystal x-ray diffraction showed that the LT-InGaP films had ∼47% In composition. The angular separation, Δθ, between
the GaAs substrate and the as-grown LT-InGaP film on (004) reflection was increased by 20 arc-s after annealing. In order
to better understand the annealing effect, a LT-InGaP film was grown on an InGaP film grown at 480°C. While annealing did
not have any effect on the HT-InGaP peak position, the LT-InGaP peak was shifted toward the HT-InGaP peak, indicating a decrease
in the LT-InGaP lattice parameter. Cross-sectional transmission electron microscopy indicates the presence of phase separation
in LT-InGaP films, manifested in the form of a “precipitate-like” microstructure. The analytical scanning transmission electron
microscopy analysis of the LT-InGaP film revealed a group-V nonstoichiometric deviation of ∼0.5 at.% P. To our knowledge,
this is the first report about the growth and characterization of LT-InGaP films. 相似文献
19.
H. -F. Li S. Dimitrijev D. Sweatman H. B. Harrison 《Journal of Electronic Materials》2000,29(8):1027-1032
This paper presents the results of the effect of NO annealing temperature and annealing time on the interfacial properties
of n-type 4H-SiC MOS capacitors. The interface trap density measured by conductance technique at 330°C decreases as NO annealing
temperature increases from 930°C to 1130° and annealing time is extended from 30 min. to 180 min. The changes in effective
oxide charge between room temperature and high temperature are calculated and used to compare different n-type 4H-SiC MOS
capacitors. Higher NO annealing temperature and longer NO annealing time decrease the change in effective oxide charge, which
is consistent with the NO annealing temperature/time dependence of interface trap density measured by conductance technique.
However, NO annealing temperature has more pronounced influence on the SiO2/SiC interface than NO annealing time. 相似文献
20.
R. S. Sussmann 《Journal of Electronic Materials》1983,12(3):603-617
Results are reported on the electrical properties of semi-insulating InP implanted with78Se and32S at different energies and doses. The implants were into both room temperature and heated substrates and annealed over the temperature range from 400°C to 760°C. Pronounced differ-ences have been found in the annealing temperature depend-ence between hot and room temperature implants. In most cases hot implants can be activated at much lower temp-eratures than previous reported results would indicate, making ion implantation, in principle, compatible with a wider range of device processing techniques. The role of dielectric coatings as both implantation barriers and annealing encapsulants has also been investigated. 相似文献