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In this work we examine the electrical characteristics and the memory properties of metal-alumina-nitride-oxide-silicon (MANOS) devices as a function of the post deposition annealing conditions. Post deposition annealing of the samples was performed at 850 or 1050 °C in nitrogen ambient using two different processes: (1) Furnace annealing for 15 min and (2) rapid thermal annealing for 1 or 5 min. The capacitance equivalent thickness as extracted from the capacitance voltage characteristics depends strongly on the annealing process, being smallest for the furnace annealing. Furthermore, the experimental results indicate that the type of the annealing determines the defect state density of the Al2O3 layer, via which the undesired effect of gate electrode electron injection takes place in the negative voltage regime. For inert ambient annealing the furnace process appears more efficient as compared to RTA.

In search for non-toxic thermoelectric materials that are stable in air at elevated temperatures, zinc oxide has been shown to be one of only few efficient n-type oxidic materials. Our bottom-up approach starts with very small (-4 Wm-1K-2 were measured at temperatures higher than 600 °C.

The focus of this work is on back contact improvement for sputtered CZTS thin film solar cells. Three methods have been investigated including a thin Ag coating, a thin ZnO coating on the Mo back contact and rapid thermal annealing of the back contact. All of these methods have been found to reduce defects such as voids as well as secondary phases at the back contact region and inhibit the formation of MoS2. Consequently all the mothods effectively enhances Voc, Jsc, FF and therefore efficiency significantly.

We have investigated the effect of post-growth rapid thermal annealing (RTA) at different temperature on two InAs/GaAs bilayer quantum dots samples with different spacer thicknesses (7.5nm and 8.5nm). It is found that when RTA temperature gradually increases, there is usual blue shift of ground state emission peak wavelength for the sample having thinner spacer but for the other sample the emission peak sustains at same peak wavelength position upto a higher annealing temperature. The dots inside the sample with less spacer thickness dissolute much earlier (beyond 700°C annealing temperature) in comparison to the other sample. The structural and optical characterization has been done by cross sectional transmission electron microscope (XTEM) and low temperature photoluminescence (PL) experiments respectively.

A Rapid Thermal Annealing (RTA) system was used to anneal sputtered and MOVPE-grown Aluminum Nitride (AlN) thin films at temperatures up to 1000°C in ambient and controlled environments. According to Energy Dispersive X-Ray Analysis (EDAX), the films annealed in an ambient environment rapidly oxidize after five minutes at 1000°C. Below 1000°C the films oxidized linearly as a function of annealing temperature which is consistent with what has been reported in literature [1]. Laser Doppler Vibrometry (LDV) was used to measure the piezoelectric coefficient, d33, of these films. Films annealed in an ambient environment had a weak piezoelectric response indicating that oxidation on the surface of the film reduces the value of d33. A high temperature furnace has been built that is capable of taking in-situ measurements of the piezoelectric response of AlN films. In-situ d33 measurements are recorded up to 300°C for both sputtered and MOVPE-grown AlN thin films. The measured piezoelectric response appears to increase with temperature up to 300°C possibly due to stress in the film.

We present B junction extensions that are extremely abrupt and shallow manufactured by amorphization, C co-implantation and conventional rapid thermal annealing (RTA). Resulting junctions have abruptnesses of 2 nm/dec better than as-implanted profiles. The most shallow B junction that has been manufactured is 15 nm deep and Rs = 626 Ω/sq. Successful implementation of these junctions is straightforward for P-MOS 30 nm gate length devices.

Rapid thermal annealing (RTA), with fast ramp up and down rates, was performed on several Cu(In,Ga)Se2 (CIGS) films and solar cells under various peak annealing temperatures and holding times. The XRD, SEM, Hall- effect, photo J-V, and quantum efficiency (Q-E) measurements were made on CIGS films and cells before and after RTA treatments to study the effects of RTA on the CIGS film properties and cell performance. The results show that RTA treatments under optimal annealing condition can provide significant improvements in the electrical properties (resistivity, carrier concentration, and mobility) of CIGS films and cell performance while preserving the film composition and microstructure morphology.

High levels of electrical activation of both p- and n-type dopants are realized by pre-amorphization implantation (PAI) in bulk germanium wafers and germanium-on-insulator (GOI) substrates. In bulk germanium, p-type dopant yields an electrical activated concentration of 1.5×1020 /cm3 after a 400°C rapid thermal annealing (RTA), which is one order higher than obtained for samples without PAI. N-type dopants also show comparable improvement as 1×1020 /cm3 after 600°C RTA. Both results are the highest ever being reported and are sufficient for advanced CMOS applications. PAI was also employed in dopant activation for GOI substrates. Carrier concentrations of 6×1020 /cm3 and 5×1019 /cm3 were observed for p- and n-type dopants respectively after identical RTA conditions as for bulk germanium counterparts. Hydrogen incorporated in GOI wafers which were prepared by Smart-Cut™ approach may be responsible for the discrepancy of activated concentrations between bulk germanium and GOI. Nevertheless, PAI shows the promise of dopant activation in germanium and can be readily adopted in current CMOS processes.

The germanosilicidation of Ni on strained (001) Si0.8Ge0.2, particularly Ge segregation, grain boundary grooving, and surface morphology, during rapid thermal annealing (RTA) was studied. High-resolution cross-sectional transmission electron microscopy (HRXTEM) suggested that Ge-rich Si1−zGez segregation takes place preferentially at the germanosilicide/Si1−xGex interface, more specifically at the triple junctions between two adjacent NiSi1−uGeu grains and the underlying epi Si1−xGex, and it is accompanied with thermal grooving process. The segregation process accelerates the thermal grooving of NiSi1−uGeu grain boundaries at the interface. The segregation-accelerated grain boundary grooving has significant effect on the surface morphology of NiSi1−uGeu films in Ni-SiGe system.

We report on magnetic properties of the GaN layers implanted with 3d transition metal ions. GaN layers grown by MOVPE on sapphire substrates, p- or n-doped, were implanted by Mn, Cr or V ions with a dose of 5×1016 cm−2 and implantation energy of 200 keV. Subsequently, a rapid thermal annealing in nitrogen atmosphere for 5 minutes at different temperatures (700°C – 1050°C) was performed. The magnetization as a function of magnetic field as well as the dependence on temperature revealed paramagnetic behavior for all samples. In addition, an antiferromagnetic coupling between implanted ions was found.

Thermal wave (TW) studies of ultra-shallow junctions (USJ) formed by ion implantation into a semiconductor wafer followed by rapid thermal annealing (RTP) are described. It is shown that using the TW technique allows for a simultaneous determination of the most important USJ parameters – depth and profile abruptness. Experimental results for junction depth and abruptness obtained on a set of B+-implanted, RTP-annealed USJ samples show better than 0.99 correlations to the corresponding secondary ion mass spectroscopy (SIMS) data.

In every wafer processing step wafer stress management is extremely important for advanced device manufacturing. Thermally induced stress on device wafers has a large impact on lithography and affects device yield. Thermally induced stress during rapid thermal annealing (RTA) steps in high density 512MB DRAM device fabrication was investigated using a lamp-based (cold wall) RTA system and compared to results using a furnace-based (hot wall) single wafer RTA system. Compared to the lamp-based (cold wall) system, RTA in a furnace-based (hot wall) system was found to be very effective in suppressing thermally induced stress and increasing device yield due to superior pattern transfer characteristics in lithography.

Results of intrinsic As diffusion in Si as well as in strained and relaxed Si0.9Ge0.1 layers are presented. Using Molecular Beam Epitaxy in-situ As doped epitaxial Si and compressively strained and relaxed Si-Ge layers were grown on Si substrates. The samples were annealed using Rapid Thermal Annealing (RTA) at 1000 °C. Arsenic diffusion is seen to be enhanced in SiGe than in Si. The enhancement factor is calculated to be 2.3 and 1.3 for relaxed and strained Si0.9Ge0.1, respectively. Also, using RTA in oxygen atmosphere, interstitial and vacancies were selectively injected in to the sample structures. Diffusion enhancement is also recorded in Si and Si-Ge structures with interstitial as well as vacancy injections over inert anneal. The results suggest that both interstitial and vacancy defects contribute to As diffusion in Si and Si0.9Ge0.1.

In this work, Raman spectroscopy was used to study the reaction of pure Ni and Ni(Pt 5 at. %) with fully-strained Si0.9Ge0.1 and Si0.899Ge0.1C0.001. With pure Ni, it was found that the incorporation of 0.1% C in the substrate resulted in out-diffusion of Ge from the germanosilicide film at a lower rapid thermal annealing (RTA) temperature compared to that of pure Ni on Si0.9Ge0.1. This Ge out-diffusion phenomenon is evident from the gradual shift in the NiSi1-wGew (w ≤ x) Raman peak from ∼213 cm−1 to higher wavenumbers, closer to 217 cm−1 as reported for pure Ni/Si, indicating that Ge is being depleted from the film with increasing RTA temperatures. In addition, it was found that severe agglomeration of the germanosilicide film occurred at a lower RTA temperature for the Ni/Si0.899Ge0.1C0.001 system. This corresponds to the observations from the Raman spectra, where a sharp increase in the Si substrate peak at 520 cm−1 was observed, coupled with the appearance of the transverse acoustic (TA)-phonon peak of Si at 301 cm−1. When Pt was introduced into the Ni film, significant improvements were observed for the germanosilicide films on Si0.9Ge0.1 and Si0.899Ge0.1C0.001 substrates, both in terms of Ge out- diffusion and agglomeration. Initial findings show that the addition of Pt promotes the formation of the low resistivity mono-germanosilicide phase at temperatures as low as 300°C.

The characteristics of dopant activation by sequential lateral solidification in poly-Si films is investigated using sheet resistance measurement and Raman measurement. Sheet resistance of n+ and p+ doped poly-Si films decreases exponentially as the laser energy increases. The minimum sheet resistance of n+ doped poly-Si films is 150 Ω/□ which is near to that of rapid thermal annealing (RTA) while the minimum sheet resistance of p+ doped poly-Si films is 180 Ω/□ which is less than a half to that of RTA. The sheet resistance of n+ and p+ doped poly-Si increases as the laser energy increases when the laser energy is above 573 mJ/cm2 at which the nucleation occurs. Raman signal of n+ doped poly-Si films shows single peak at 515 cm-1 with all laser energy and has maximum intensity at 566 mJ/cm2 laser energy. Raman signal of p+ doped poly-Si films shows single peak below 413 mJ/cm2 laser energy and double peak above 444 mJ/cm2 laser energy where the fully melting of p+ doped poly-Si film occurs.

We comparatively studied the formation of ultra thin Co silicides, Co2Si, CoSi and CoSi2, with/without a Ti-capped and Ti-mediated layer by using rapid thermal annealing in a N2 ambient. Four-point-probe sheet resistance measurements and plan-view electron diffraction were used to characterize the silicides as well as the epitaxial characteristics of CoSi2 with Si. We found that the formation of the Co silicides and their existing duration are strongly influenced by the presence of a Ti-capped and Ti-mediated layer. A Ti-capped layer promotes significantly CoSi formation but suppresses Co2Si, and delays CoSi2, which advantageously increases the silicidation-processing window. A Ti-mediated layer acting as a diffusion barrier to the supply of Co suppresses the formation of both Co2Si and CoSi but energetically favors directly forming CoSi2. Plan-view electron diffraction studies indicated that both a Ti-capped and Ti-mediated layer could be used to form ultra thin epitaxial CoSi2 silicide.

In this paper, a novel annealing method, scanning-rapid thermal annealing (RTA), for the selectively nucleated lateral crystallization (SNLC) of Pb(Zr,Ti)O3 (PZT) thin films is discussed. The effects of lamp power and scan speed on the SNLC were investigated. It was found that scanning-RTA was very effective method for SNLC in reducing the process time and preventing undesirable nucleation at other than pre-determined positions.

Nickel Induced Lateral Crystallization (NILC) and Pulsed Rapid Thermal Annealing (PRTA) have been used to study new low temperature and high quality poly-silicon (poly-Si) films and thin film transistors (TFTs). The growth rate of poly-Si films has been found to greatly increase from 0.025μm/minute to 1.07μm/minute, and the drain current and performance of TFTs have increased by around 75%. The new poly-Si technology has good potential to apply in high performance, large area, fast throughput, low cost and even low temperature device applications.

YMnO3 thin films were sputtered on Si (100) substrates under different ambient conditions. After rapid thermal annealing process at 850 °C, the YMnO3 film deposited in Ar ambient had random orientations and the YMnO3 film deposited in Ar+O2 ambient was crystallized with distinct two layers, i.e., c-axis oriented layer in top region and random oriented layer in bottom region. Relations between the microstructure and the electrical properties of Pt/YMnO3/Si capacitor were investigated. Memory window and leakage current depended on the orientation of the YMnO3 thin films and the interfacial microstructure of the YMnO3/Si, respectively

The electrical and optical properties of Si-implanted GaN have been investigated as a function of ion dose, anneal temperature, and implantation temperature using Hall-effect measurements and photoluminescence. Implantation of 200 keV Si ions was made at room temperature and 800°C into MBE-grown GaN capped with 500 Å AlN at six different doses ranging from 1x1013 to 5x1015 cm-2. The samples were proximity cap annealed from 1050 to 1350°C for 5 min to 20 s using either a conventional furnace or rapid thermal annealing. For a given dose, electrical activation efficiencies and mobilities increase as the anneal temperature increases from 1050 to 1350°C. Generally, the higher the dose, the greater the activation efficiency for any given anneal temperature. For a sample implanted with a dose of 1x1015 cm-2 and annealed at 1350°C for 20 s, an electrical activation efficiency of 100% was obtained. Exceptional carrier concentrations and mobilities were obtained on all Si-implanted samples, and a comparison of the results was made between room temperature and 800°C implantation. Photoluminescence measurements were also performed in an effort to better understand the electrical activation behavior of the Si implants in GaN.

Rapid thermal annealing (RTA) of lattice damage created by heavy ion implantation damage is required to maintain the integrity of semiconductor material used for submicron-integrated circuit devices. A quick, efficient, and contactless diagnostic of the implantation damage is highly desirable in both research and production environments. A contactless measurement technique has been recently applied to this problem that uses a deeply penetrating low-frequency microwave probe frequency operating at 420 MHz. Here, we will demonstrate the use of this high frequency resonance-coupled photoconductive decay (RCPCD) technique, which, when combined with a tunable optical excitation source, enables us to map the radiation damage in boron and arsenic-implanted silicon wafers. We quantify the damage by mapping the minority-carrier lifetime as a function of optical penetration depth. In this work, we quickly and efficiently compared the effectiveness of various RTA processes by the RCPCD diagnostic.

This paper studies the use of ion implantation and rapid thermal annealing for the fabrication of shallow junctions in sub-100 nm CMOS technology. Spike annealing recipes were optimized on the basis of delta-doping diffusion experiments and shallow junction characteristics. In addition, using GeF2 pre-amorphization implants in combination with low-energy BF2 and spike annealing, p-type junctions depths of 30 nm were obtained with sheet resistances as low as 390 Ω/sq. The combined finetuning of implantation and annealing conditions is expected to enable junction scaling into the 70-nm CMOS technology node.

The optically detected magnetic resonance (ODMR) technique has been employed to examine the nature and formation mechanism of non-radiative defects in GaNAs and InGaAsN. In both alloys, two defects were observed and were shown to be deep-level, non-radiative recombination centers. One of the defects has been identified as a complex involving an AsGa antisite. These two defects gain more importance with increasing N composition up to 3%, presumably due to an increase in their concentration. With a further higher N composition, the defects start to lose importance in carrier recombination that is attributed to an increasingly important role of other new non-radiative channels introduced with a high N composition. On the other hand, effect of In composition up to 3% seems to be only marginal. Both defects were shown to be preferably introduced in the alloys during low-temperature growth by molecular beam epitaxy (MBE), but can be rather efficiently removed by post-growth rapid thermal annealing.

Antimony implantation is a promising technique for fabricating ultra-shallow n+/p junctions for extensions of sub-100-nm n-MOSFETs. By increasing the Sb+ implantation dose to 6×1014 cm−2, sheet resistance (Rs) of an implanted layer was reduced to 260 /sq. for rapid thermal annealing (RTA) at 800°C. The obtained junction depth of 19 nm is suitable for sub-100-nm MOSFETs. However, the reduction in the sheet resistance showed a tendency to saturate. No pileup at the Si-SiO2 interface, which was the major origin of dopant loss in lower dose cases was, observed in Sb depth profiles in this case. However, in the case of 900°C RTA, Sb depth profiles indicated that Sb was nearly immobile in the region where Sb concentration exceeded 1×1020 cm−3. These results imply that the major limiting factor of Rs reduction under the highdose condition is Sb precipitation, which is different from the lower dose cases.

In this study, the KLN thin films were prepared by RF-magnetron sputtering method onto Coming 1737 glass. The effect of working pressure, substrate temperature, RF-power, sputter gas ratio (Ar/O2) during deposition was investigated. For an optimum deposition condition, the postannealing, RTA(rapid thermal annealing) and IPA(in-situ post annealing)methods were employed. Both RTA and IPA processes, which were conducted at different deposition and annealing temperature influenced surface morphology and optical properties of the films. The films prepared by the IPA process showed a lower crystallization temperature and better optical transmittance.

Over the last couple of years rapid thermal annealing (RTA) equipment suppliers have been aggressively developing lamp-based furnaces capable of achieving ramp-up rates on the order of hundreds of degrees per second. One of the driving forces for adopting such a strategy was the experimental demonstration of 30nm p-type junctions by employing a ramp-up rate of ≈400°C/s. It was subsequently proposed that the ultra-fast temperature ramp-up was suppressing transient enhanced diffusion (TED) of boron which results from the interaction of the implantation damage with the dopant. The capability to achieve very high temperature ramp-rates was thus embraced as an essential requirement of the next generation of RTA equipment.In this paper, recent experimental data examining the effect of the ramp-up rate during spike-and soak-anneals on enhanced diffusion and shallow junction formation is reviewed. The advantage of increasing the ramp-up rate is found to be largest for the shallowest, 0.5-keV, B implants. At such ultra-low energies (ULE) the advantage arises from a reduction of the total thermal budget. Simulations reveal that a point of diminishing return is quickly reached when increasing the ramp-up rate since the ramp-down rate is in practice limited. At energies where TED dominates, a high ramp-up rate is only effective in minimizing diffusion if the implanted dose is sufficiently small so that the TED can be run out during the ramp-up portion of the anneal; for larger doses, a high ramp-up rate only serves to postpone the TED to the ramp-down duration of the anneal. However, even when TED is minimized at higher implant energies via high ramp-up rates, the advantage is unobservable due to the rather large as-implanted depth. It appears then that while spike anneals allow the activation of ULE-implanted dopants to be maximized while minimizing their diffusion the limitation imposed by the ramp-down rate compromises the advantage of very aggressive ramp-up rates.

The residual stress in doped and undoped polysilicon films, before and after rapid thermal annealing (RTA), is investigated using both wafer-curvature and micro-rotating structures techniques. Microstructure characterization has been conducted as well to understand the mechanism of the stress evolution. The results show that the compressive residual stresses in undoped polysilicon films can be reduced or eliminated within a few seconds RTA. Surface nitridation and grain growth are identified as the mechanisms responsible for the stress evolution.

The effects of ramp-up rate during rapid thermal processing of ultra-shallow boron implants have been investigated. Ramp-up rates were varied between 25 °C and 200 °C for two types of anneals: soak anneals and spike anneals. It was found that the ramp-up rate had very little influence on junction depth or electrical activation for both types of anneals. Spike anneals did produce shallower profiles than soak anneal for a comparable electrical activation and may be an option for future processes.

Based on the criteria for the solid state exchange reaction with p-GaN, we have investigated the intermetallic compound Niln as a possible ohmic contact. The contacts were fabricated by depositing Niln on p-GaN films (p ∼ 2 × 1017 cm-3) using RF sputtering from a compound target. The as-deposited, Niun contacts were found to be rectifying and using I-V characterization a Schottky barrier height of 0.82 eV was measured. Rapid thermal annealing of the contacts was shown to significantly decrease their resistance, with contacts annealed at 800°C for I min yielding the lowest resistance. When annealed at 800°C for 1 min Niln contacts exhibited a specific contact resistance of 8-9 × 10-3 Ωcm2, as measured by the circular transmission line model. To allow a more universal comparison the more traditional Ni/Au contacts, processed under the same conditions, were used as a standard. Their measured specific contact resistance (ρc = 1.2 - 2.1 x 10-2 Ωcm2) was significantly higher than that of the Niln contacts. Demonstrating that Niln has promise as an ohmic contact to p-GaN and should be studied in greater detail.

The (Pb1−xLax)TiO3, (PLT) thin films possessing good ferroelectric properties were successfully obtained by using metal-organic-decomposition (MOD) process, followed by furnace post-annealing at 600-700°C (60 min) or rapid thermal annealing (RTA) at 600-700°C (60 s). Excess Pb-species incorporated in precursors for compensating for the Pb-loss during MOD process results in pronounced modification on thin film's electrical properties. The leakage current is reduced from JL= 1 × 10−3 A/cm2 to 1 × 10−4 A/cm2 (at 400 kV/cm) and the remanent polarization is increased from Pr= 8.3 µ C/cm2 to 12.6 µC/cm2, when 10 mol% excess-Pb is added. On the other hand, larger La-content in PLT films results in more pronounced Pb-loss and induces larger leakage current, which significantly degrades the ferroelectric properties of the films. The best properties obtained for PLT films prepared by the MOD process are: Pr= 12.6 µC/cm2, Ec = 80 kV/cm and JL= 10−5 A/cm2 (at 400 kV/cm).

We report a new Ni/Pt/Au (20/30/80 nm) metallization scheme to achieve a low ohmic contacts to p-type GaN with a carrier concentration of 9.4 × 1016 cm-3. A Mg-doped GaN layer (0.5 μm) was grown on (0001) sapphire substrate by metalorganic chemical vapor deposition (MOCVD). All metal thin films were deposited on the p-GaN layer in an electron-beam evaporation system. Samples were annealed by a rapid thermal annealing (RTA) process at a range of temperatures from 300 °C to 850 °C under a flowing Ar atmosphere. A circulartransmission line model (c-TLM) was employed to calculate the specific contact resistance, and current-voltage (I-V) data were measured with HP4155A. The Ni/Pt/Au contacts without the annealing process showed nearly rectifying characteristics. The ohmic contacts were formed on the samples annealed at 500 °C for 30 sec and the I-V data showed a linear behavior. The specific contact resistance was 2.1 × 10-2 Ωcm2. However with increasing the annealing temperature above 600 °C, ohmic contacts were again degraded. Auger electron spectroscopy (AES) depth profiles were used to investigate the interfacial reactions between the trilayer and GaN. AES results suggested that Pt plays a significant role in forming ohmic contact as an acceptor at the interface. Atomic force microscope (AFM) also showed that the samples with good ohmic contact have very smooth surface.

Deep levels in undoped LEC semi-insulating (SI) GaAs have been investigated by rapid thermal annealing (RTA). The GaAs wafers were annealed for 10 sec in N2 atmosphere at temperatures ranging from 500 to 800 °C. Using photo-induced current transient spectroscopy (PITS) and Hall measurement, we have investigated the behavior of various deep levels as a function of RTA temperature and the phenomenon of thermal conversion. The change and even conversion in resistivity is related not only to decrease of the EL2 and EL6 defects, but also to shallow acceptor caused by arsenic-escaping in the surface of the wafer. Choosing proper RTA temperaturte will improve the electrical properties of SI-GaAs after RTA.

Ferroelectric Bi4Ti3O12 thin films were grown by atmospheric pressure metal-organic chemical vapor deposition. After rapid thermal annealing (RTA), the films have a (001) preferred orientation, The I-V and C-V characteristics were studied, the resistivity were in the rang of 1010∼1013 ω. cm, at room temperature. The memory window is about 3V. These results snow that The Bi4Ti3O12 films prepared at present work are suitable for making ferroelectric FEFETs memories. By using planar silicon processing, the FEFET devices have been fabricated, which shows clearly memory effect under a applied ±5V gate voltage.

With 150KeV Mg+ ion implantation, the optical and structural characteristics of GaN films were studied. Post-implant annealing up to 1000°C was performed in N2 ambient with a rapid thermal annealing (RTA) system, without an encapsulation layer. We observed a green band photoluminescence from Mg-implanted GaN. This green band photoluminescence should be associated with Mg induced defect-clustering in GaN. We also use the x-ray diffraction method to study the correlation between structure defects and implantation. We observed an extra shoulder peak at the small angle side of the GaN[0004] diffraction peak. The origin of this shoulder may be attributed to implanted magnesium induced GaN lattice strain.

Compositional interdiffusion in Al0.3 Ga0.7 As/GaAs superlattices induced by Si focused ion beam implantation and subsequent rapid thermal annealing is modeled using a set of diffusion equations which take into account the dynamics of the vacancy spatial profile. The inclusion of a new phenomenological term, which depends on the time derivative of the vacancy concentration spatial profile, provides good agreeement with experiment.

Atomic profiles (SIMS) and cross-section TEM images of selectively etched, annealed profiles were studied for Boron energies from 20 da eV (200 eV) to 10 keV and RTP anneals at 900, 975 and 1050 C Consistent variations of dopant depth was obtained over this process range. TEM images showed evidence of lateral dopant variation near the edges of poly-Si gate structures, perhaps an effect of lateral straggling and reflection of ions from the poly mask.

Si was implanted with 115In+ ions with a dose exceeding the value of the In solid solubility. Rapid thermal annealing with W-halogen lamp was done sequentially with the wafer facing in two different positions relative to the source of the light irradiation. It has been experimentally found that short and long wavelength components of incoherent light act in a different manner on the In atom activation in Si during RTA process. The effect of In activation and deactivation caused by the RTA treatment is reversible in the temperature region of 440–1020°C. The effect of In activation and deactivation exists after thirty RTA pulses.

The activation annealing of Si-implanted GaN is reported for temperatures from 1100 to 1400 °C. Although previous work has shown that Si-implanted GaN can be activated by a rapid thermal annealing at ∼1100 °C, it was also shown that significant damage remained in the crystal. Therefore, both AlN-encapsulated and uncapped Si-implanted GaN samples were annealed in a metal organic chemical vapor deposition system in a N2/NH3 ambient to further assess the annealing process. Electrical Hall characterization shows increases in carrier density and mobility for annealing up to 1300 °C before degrading at 1400 °C due to decomposition of the GaN epilayer. Rutherford backscattering spectra show that the high annealing temperatures reduce the implantation induced damage profile but do not completely restore the as-grown crystallinity.

The relationship between the hydrogen-related metastable defect (M3/M4) and the EL2 level in n-GaAs crystals has been investigated. We found with various kinds of GaAs crystals that the hydrogen-related metastable couple (M3/M4), first reported by Buchwald et al., has been observed only in the crystals containing the EL2 defect. This fact was further confirmed by using LT-MBE GaAs crystals before and after rapid thermal annealing (RTA). Only in the n-LT-n sample annealed at 900°C, in which the EL2 defect was formed, the metastable couple (M3/M4) appeared upon hydrogenation. As hydrogenated, the EL2 level was passivated or dissociated. From bias-annealing experiments, the M4 level was completely annihilated by annealing at 573K, where the EL2 level was restored to its original concentration. We speculated from these results that both diffused hydrogen and preexisting arsenic antisite defect (AsGa) are responsible for the formation of the metastable defect(M3/M4).

Rapid thermal annealing (RTA) induced reactions between Ti thin films and Si wafers were characterized by sheet resistance measurements. It was found that the standard deviation σ of the measurements is RTA-temperature dependent, and strongly correlates with the mean sheet resistance % MathType!MTEF!2!1!+- % feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaa0aaaeaaca % WGsbaaaaaa!36DE! $$\overline R $$ . A specific temperature was identified, corresponding to a sharp σ peak in the temperature regime associated with the C49-C54 TiSi2 phase transition. This temperature is characteristic of materials parameters such as Ti thickness and substrate doping species, and can be used to accurately monitor or compare the calibration of RTA systems.

We present annealing behavior for EL2 and EL6 groups as dominant deep levels in semiinsulating GaAs using Photo Induced Transient Spectroscopy (PITS) measurement. During rapid thermal annealing, a relation has been identified between EL2 group at 0.79 and 0.82 eV and EL6 group at 0.24, 0.27 and 0.82 eV below the conduction band. It is found that they may be close in structure, and belong to the EL2 and EL6 groups, respectively. In rapidly annealed samples, the quantity of all defects in the EL2 group increases, while that in the EL6 group decreases. However, by furnace annealing at 950°C for 5 hours, some of the defects in the EL2 group break up, and the quantity of all defects in the EL6 group increases. It is suggested that the EL2 group and EL6 group are related in their microscopy structures. We then discuss a relation between the two groups and their origins.

A shift in the peak response wavelength and a broadening of the photoresponse spectrum is demonstrated for intersubband absorption in n-doped GaAs/AIGaAs multiple quantum well detectors following intermixing of the well and barrier layers during rapid thermal annealing. In general, a decrease in performance is observed for the RTA QWIPs when compared to the as-grown detectors. The peak absolute response of the annealed QWIPs is lower by almost a factor of four, which results in corresponding decrease in quantum efficiency. In addition, the noise performance results in a detectivity which is five times lower than that of QWIPs fabricated from as-grown structures.

Furnace annealing (FA) and rapid thermal annealing (RTA) were made for Cd+ ion-implanted GaAs with Cd concentration, [Cd] from 1×1016cm−3 to 3×1021 cm−3. In FA samples, Raman scattering spectra exhibited a single peak at 292 cm−1 for entire [Cd] range which is LO-phonon mode from (100) GaAs. In RTA samples, LO-phonon mode is a single peak for [Cd]19cm−3 but with growing [Cd], TO-phonon mode appears for [Cd] 1×1020cm3 and becomes a dominant signal for [Cd]=3×1021 cm−3. The quenching of LO-phonon mode with increasing [Cd] was more clearly observed in RTA samples than in FA ones. Hall-effects results, however, showed that activation rate of RTA samples is 6–7 times larger than that of FA ones for [Cd] 1×1021 cm−3. 2K photoluminescence spectra revealed that in FA samples multiple shallow emissions associated with Cd are formed while in RTA ones the dominant emission is the band to Cd acceptor transition.

In this article a new procedure to obtain alpha-hexathienylene (α-6T) thin-film-transistors (TFTs) with on/off ratios in excess of one million is reported. This procedure involves subjecting the TFTs to rapid thermal annealing. Previously, high on/off ratios have been achieved with improved device design and better chemical synthesis of α-6T oligomers. High on/off ratios, along with a switching time of ∼ 10 μs, render α-6T TFTs potential candidates as switching devices in active matrix displays. The experimental current-voltage (I-V) characteristics of oc-6T TFTs with channel length L = 4μm are also presented and a measured field effect mobility of 0.02 cm2/V-s is extracted from these characteristics using an analytical model which we have developed for short-channel α-6T TFTs.

The structural evolution of Ni/Au/Te/Au contacts on n-GaAs (001) was examined, in correlation with their electrical properties as a function of rapid thermal annealing in the temperature range 350 - 600°C. It was found that heating at temperatures ≥ 550°C results in the formation of ohmic contacts, while contacts annealed at lower temperatures remain nonohmic. Transmission electron microscopy revealed that heating ≥ 450°C leads to extensive reactions between Ni/Au/Te/Au and GaAs and deep spike formation into the GaAs. The major reaction products were identified as NiAs and β-AuGa. Ga2Te3 grains, growing epitaxially on GaAs, were detected only in 550°C annealed samples. Heating to 600°C caused considerable Ga2Te3 loss. Implications of these results concerning the ohmic contact formation mechanism are discussed.

Ripple pyrometry was proposed by Accufiber as a method for measuring wafer temperature in lamp-heated ovens. The technique obtains the wafer temperature from the wafer emittance radiation by simultaneously determining the effective emittance of the wafer and suppressing the interference from reflected lamp radiation. This paper reviews the technique for rapid thermal annealing and presents experimental results on silicon wafers instrumented with thermocouples and on processing blanket-film monitor wafers.

Cross section TEM and channeling analysis show that the heating rate (HR) of a rapid thermal annealing (RTA) cycle affects the residual defect distribution in Si implanted with As+ to a heavy dose (≈ 1016 cm−2). Two defect bands are observed after solid phase epitaxial growth (SPEG): the first one centered at a depth corresponding to the projected range of the As (band I), and the second one located at depth corresponding to the original amorphous crystalline (a-c) interface (band II). The density of defects in band I is found to increase with the As dose, and with the annealing temperature (550 - 650°C, furnace annealing). However, for RTA (800 - 1000°C) both the density and depth distribution of these defects are dependent on HR. We propose that Si self-interstitials (SiI) are created at the a-c interface when As becomes substitutional during SPEG. The SPEG velocity determines whether the SiI are accommodated in the amorphous Si layer (low velocities) or are captured by the regrowing c-Si (high velocities)

Silicon samples were single implanted with B+ (5 x 1014 cm−2, 50 keV) or co-implanted with C+ (5 x 1015 cm−2, 55 keV). Rapid thermal annealing (RTA) with heating rates (HR) of 1°C/s and 100°C/s with dwell time duration from 2 s to 15 min was used for B activation and the results compared with those provided by conventional furnace annealing (FA) for 30 min. In single implanted samples it was found that below 600°C or above 800°C the activation always increases with the annealing time. However, in the temperature range of 600-800°C and annealing times longer than 60 s a fraction of the initially activated B concentration deactivates. For temperatures in the range of 700-800°C the deactivation is followed again by another activation period. There is no noticeable difference between the activation yields after RTA with high HR for 15 min or FA for 30 min. In the C co-implanted samples the activation of boron saturates after few minutes. In addition the deactivation process is significantly reduced. A model assuming interaction of the B atoms with point defects and the C atoms with Si self- interstitial atoms is proposed to explain the results.

Pseudomorphic Ge0.12Si0.88 films 265 nm thick grown by molecular beam epitaxy on p- Si(100) substrates were implanted with 100 keV 31P at room temperature for a dose of 5 x 1013/cm2. The projected range of the implanted P is about half the epilayer thickness. The implanted layers, together with non-implanted virgin samples, were subsequently annealed by both rapid thermal annealing in nitrogen and by steady-state furnace annealing in vacuum. The damage and strain of the annealed layers were studied by 4He channeling and x-ray doublecrystal diffraction. For a dose of 5 x 1013 P /cm2, both the damage and strain introduced by implantation can be completely removed, within instrumental sensitivity, by rapid thermal annealing at 700 °C for 10 - 40 s. Furnace annealing at 550 °C for 30 min for this sample removes most of the damage and strain induced by implantation. Furnace annealing at 700 °C or higher worsens the crystallinity of the layer and the strain relaxes. Hall measurements were performed on the same samples. Furnace annealing cannot achieve good dopant activation without introducing significant strain relaxation to the heterostructure, while rapid thermal annealing can.

Secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS) are used to investigate Ti silicide formation mechanisms on a series of Ti on Si thin films annealed in ultrahigh vacuum (UHV) at different temperatures and durations. The competition between oxygen diffusion and the silicide formation reaction (the socalled “snowplough” effect) is observed directly, as well as a Ti-Si-O layer. The results from these controlled experiments are compared with those from Ti silicide films formed under rapid thermal annealing (RTA) conditions in a production furnace, with and without a TiW barrier layer.