Germanium Implantation into Silicon: An Alternate Pre-Amorphization/Rapid Thermal Annealing Procedure for Shallow Junction Technology

1983 ◽  
Vol 23 ◽  
Author(s):  
D.K. Sadana ◽  
E. Myers ◽  
J. Liu ◽  
T. Finstad ◽  
G.A. Rozgonyi
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Surface Region ◽  
Amorphous Layer ◽  
High Dose ◽  
Dislocation Loops ◽  
Cross Sectional ◽  
Defect Clusters ◽  
Ion Damage ◽  
Free Material

ABSTRACTGermanium implantation into Si was conducted to pre-amorphize the-si surface layer prior to a shallow/high dose (42 keV, 2 × 1015 cm−2) BF2 implant. Cross-sectional transmission electron microscopy showed that rapid thermal annealing (RTA) of the amorphous layer (without BF2 ) leaves defect-free material in the implanted region. Only a discrete layer of small (∼300Å) dislocation loops due to straggling ion damage was found to be present at a depth corresponding to the amorphous/crystalline interface. RTA of the amorphous layer with the BF2 creatpd a high density of uniformly. distributed fine defect clusters (∼50Å) in the surface region (0–500Å) in addition to the straggling ion damage. Boron and F profiles obtained by secondary ion mass spectrometry from the unannealed and rapid thermally annealed samples showed the presence of high concentrations of these impurities in the surface region where the fine defect clusters were observed. A comparison of the RTA behavior of the pre-amorphized surface layers (with or without BF2 ) produced by Ge and self-implantation is presented.

Shallow Junction Formation in As-Implanted Si by Low-Temperature Rapid Thermal Annealing

1989 ◽  
Vol 147 ◽  
Author(s):  
M. K. El-Ghor ◽  
S. J. Pennycook ◽  
R. A. Zuhr
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Dislocation Loops ◽  
Cross Sectional ◽  
Dopant Activation ◽  
Transmission Electron ◽  
Shallow Junctions ◽  
Surface Image ◽  
Long Time ◽  
Short Time

AbstractShallow junctions were formed in single-crystal Si(100) by implantation of As at energies between 2 and 17.5 keV followed by conventional furnace annealing or by rapid thermal annealing (RTA). Cross-sectional transmission electron microscopy (XTEM) showed that defect-free shallow junctions could be formed at temperatures as low as 700 °C by RTA, with about 60% dopant activation. From a comparison of short-time and long-time annealing, it is proposed that surface image forces are responsible for the efficient removal of end-of-range (EOR) dislocation loops

Influence of the Temperature of Implantation on the Morphology of Defects in MeV Implanted GaAs.

1989 ◽  
Vol 147 ◽  
Author(s):  
G. Braunstein ◽  
Samuel Chen ◽  
S.-Tong Lee ◽  
G. Rajeswaran.
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Point Defects ◽  
Room Temperature ◽  
Surface Region ◽  
Amorphous Region ◽  
Liquid Nitrogen Temperature ◽  
Dislocation Loops ◽  
Near Surface ◽  
Epitaxial Regrowth

AbstractWe have studied the influence of the temperature of implantation on the morphology of the defects created during 1-MeV implantation of Si into GaAs, using RBS-channeling and TEM. The annealing behavior of the disorder has also been investigated.Implantation at liquid-nitrogen temperature results in the amorphization of the implanted sample for doses of 2×1014 cm−2 and larger. Subsequent rapid thermal annealing at 900°C for 10 seconds leads to partial epitaxial regrowth of the amorphous layer. Depending on the implantation dose, the regrowth can proceed from both the front and back ends of the amorphous region or only from the deep end of the implanted zone. Nucleation and growth of a polycrystalline phase occurs concurrently, limiting the extent of the epitaxial regrowth. After implantation at room temperature and above, two distinct types of residual defects are observed or inferred: point defect complexes and dislocation loops. Most of the point defects disappear after rapid thermal annealing at temperatures ≥ 700°C. The effect of annealing on the dislocation loops depends on the distance from the surface of the sample. Those in the near surface region disappear upon rapid thermal annealing at 700°C, whereas the loops located deeper in the sample grow in size and begin to anneal out only at temperatures in excess of 900°C. Implantation at temperatures of 200 - 300°C results in a large reduction in the number of residual point defects. Subsequent annealing at 900°C leads to a nearly defect-free surface region and, underneath that, a buried band of partial dislocation loops similar to those observed in the samples implanted at room temperature and subsequently annealed.

Device Parametric Shift Mechanism Caused by Boron Halo Redistribution Resulting from Dose Rate Dependence of SDE Implant

2005 ◽  
Vol 864 ◽  
Author(s):  
Ukyo Jeong ◽  
Jinning Liu ◽  
Baonian Guo ◽  
Kyuha Shim ◽  
Sandeep Mehta
Keyword(s):  
Surface Region ◽  
Amorphous Region ◽  
Amorphous Layer ◽  
High Dose ◽  
Extended Defects ◽  
Dislocation Loops ◽  
Near Surface ◽  
Enhanced Diffusion ◽  
Dose Rates ◽  
Pile Up

AbstractChange in dopant diffusion was observed for Arsenic source drain extension (SDE) implants when they were performed at various dose rates. The high dose SDE implant amorphizes the surface of the silicon substrate and the thickness of the amorphous layer is strongly influenced by the rate of dopant bombardment. It is well known that the ion implantation process introduces excess interstitials. While the amorphous region is completely re-grown into single crystal during subsequent anneal without leaving behind extended defects, interstitials that are injected beyond the amorphous layer lead to formation of {311} defects or dislocation loops in the end of range region. During thermal processing, these extended defects dissolve, release interstitials, which in turn lead to transient enhanced diffusion of underlying Boron halo dopant. Dopant depth profiles measured by SIMS revealed different amount of Boron pile-up in the near surface region, corresponding to different SDE implant dose rates. In CMOS devices, this surface pile-up would correlate with a Boron pile-up in the channel region that would lead to a shift in transistor characteristics. Through this investigation, we were able to explain the mechanism causing device characteristics shift resulted from SDE implant with the same dose and energy but different dose rates.

Rapid Thermal Annealing of B or N Implanted Monocrystalline 1-SiC Thin Films and its Effect on Electrical Properties and Device Performance

1985 ◽  
Vol 52 ◽  
Author(s):  
Jae Ryu ◽  
H. J. Kim ◽  
R. F. Davis
Keyword(s):  
Thin Films ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Amorphous Layer ◽  
High Resistivity ◽  
Electrical Measurements ◽  
Cross Sectional ◽  
Annealing Temperatures ◽  
Type Layer ◽  
P Type

ABSTRACTThe annealing behavior of B or N dual implants in 1-SiC thin films has been studied using cross-sectional transmission electron microscopy (XTEM), secondary ion mass spectroscopy (SIMS), and four point probe electrical measurements. A high resistivity layer was produced after annealing the B implanted-amorphous layer in the temperature range from 1000°C to 1500°C for 300 a; however, the resistivity rapidly decreased as a result of annealing at higher temperatures. The reasons for these changes in resistivity and the lack of p-type conduction at all annealing temperatures in these B implants include: (1) possible compensation of the native n-type carriers, (2) reduction in the B concentration via formation of B-containing precipitates between 1300°C and 1600°C and out diffusion of this species at and above 1600°C, and (3) creation of additional n-type carriers.No precipitates or defect structure was observed in N implanted-annealed samples. The resistivity of this non amorphous n-type layer decreased with increasing annealing temperatures from 700°C to 1800°C. Furthermore n-p junction diodes were fabricated for the first time in β-SiC via N implantation into samples previously in situ doped with 8 × 1018/cm3 Al coupled with rapid thermal annealing at 1200°C for 300 a. A typical diode ideality constant and a saturation current for these diodes was 3.4 and 9 × 10-10 A/cm2, respectively.

Semi-Empirical Model for Boron Diffusion During Rapid Thermal Annealing of BF2 Implanted Silicon

1993 ◽  
Vol 303 ◽  
Author(s):  
Tzu-Hsin Huang ◽  
H. Kinoshita ◽  
D. L. Kwong
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Dislocation Loops ◽  
Boron Diffusion ◽  
Enhanced Diffusion ◽  
Defect Clusters ◽  
Annealing Conditions ◽  
Wide Range ◽  
Point Defect Clusters ◽  
Semi Empirical

ABSTRACTThe mechanism of the enhanced diffusion of boron during rapid thermal annealing (RTA) of BF2-implanted Si has been investigated, and a diffusion model is accordingly developed for a wide range of implant and annealing conditions. Simulation results are in excellent agreement with experiments for BF2 implant doses from 2×1013 to 5×1015cm−2, implant energies from 6 to 45 keV, and annealing temperatures from 950 to 1100°C. This model not only accounts for the transient enhanced diffusion due to the annealing of point-defect clusters and dislocation loops, but also for the retarded diffusion due to dopant precipitation. All the parameters used in this model are analytically determined.

Annealing Of Radiation Damage in Tungsten

1970 ◽  
Vol 28 ◽  
pp. 412-413
Author(s):  
Robert C. Rau ◽  
John Moteff
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Radiation Damage ◽  
Thermal Annealing ◽  
Neutron Fluence ◽  
Dislocation Loops ◽  
Defect Clusters ◽  
Polycrystalline Tungsten ◽  
Transmission Electron ◽  
Radiation Induced

Transmission electron microscopy has been used to study the thermal annealing of radiation induced defect clusters in polycrystalline tungsten. Specimens were taken from cylindrical tensile bars which had been irradiated to a fast (E > 1 MeV) neutron fluence of 4.2 × 1019 n/cm2 at 70°C, annealed for one hour at various temperatures in argon, and tensile tested at 240°C in helium. Foils from both the unstressed button heads and the reduced areas near the fracture were examined.Figure 1 shows typical microstructures in button head foils. In the unannealed condition, Fig. 1(a), a dispersion of fine dot clusters was present. Annealing at 435°C, Fig. 1(b), produced an apparent slight decrease in cluster concentration, but annealing at 740°C, Fig. 1(C), resulted in a noticeable densification of the clusters. Finally, annealing at 900°C and 1040°C, Figs. 1(d) and (e), caused a definite decrease in cluster concentration and led to the formation of resolvable dislocation loops.

omparisons of Silicide Formation by Rapid Thermal Annealing and Conventional Furnace Annealing

1987 ◽  
Vol 92 ◽  
Author(s):  
E. Ma ◽  
M. Natan ◽  
B.S. Lim ◽  
M-A. Nicolet
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Silicide Formation ◽  
X Ray Diffraction ◽  
Furnace Annealing ◽  
Cross Sectional ◽  
Conventional Furnace ◽  
Diffusion Controlled ◽  
Conventional Furnace Annealing ◽  
Kinetics Of

ABSTRACTSilicide formation induced by rapid thermal annealing (RTA) and conventional furnace annealing (CFA) in bilayers of sequentially deposited films of amorphous silicon and polycrystalline Co or Ni is studied with RBS, X-ray diffraction and TEM. Particular attention is paid to the reliability of the RTA temperature measurements in the study of the growth kinetics of the first interfacial compound, Co2Si and Ni2Si, for both RTA and CFA. It is found that the same diffusion-controlled kinetics applies for the silicide formation by RTA in argon and CFA in vacuum with a common activation energy of 2.1+0.2eV for Co2Si and 1.3+0.2eV for Ni Si. Co and Ni atoms are the dominant diffusing species; during silicide formation by both RTA and CFA. The microstructures of the Ni-silicide formed by the two annealing techniques, however, differs considerably from each other, as revealed by cross-sectional TEM studies.

Observation of the Wurtzite Phase in OMVPE Grown ZnSe/GaAs: Effect on Implantation and Rapid Thermal Annealing

1989 ◽  
Vol 147 ◽  
Author(s):  
K. S. Jones ◽  
J. Yu ◽  
P. D. Lowen ◽  
D. Kisker
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Electrical Transport ◽  
High Resistivity ◽  
Ion Milling ◽  
Electrical Transport Properties ◽  
Wurtzite Phase ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Diffraction Patterns

AbstractTransmission electron diffraction patterns of cross-sectional TEM samples of OMVPE ZnSe on GaAs indicate the existence of the hexagonal wurtzite phase in the epitaxial layers. The orientation relationship is (0002)//(111); (1120)//(220). Etching studies indicate the phase is internal not ion milling induced. The average wurtzite particle size is 80Å-120Å. Because of interplanar spacing matches it is easily overlooked. Electrical property measurements show a high resistivity (1010ω/square) which drops by four orders of magnitude upon rapid thermal annealing between 700°C and 900 °C for 3 sec. Implantation of Li and N have little effect on the electrical transport properties. The Li is shown to have a high diffusivity, a solid solubility of ≈1016/cm3 at 800°C and getters to the ZnSeA/aAs interface.

Flux Dependence of Amorphous Layer Formation and Damage Annealing in Room Temperature Implantation of Boron into Silicon

1993 ◽  
Vol 316 ◽  
Author(s):  
Robert Simonton ◽  
Jinghong Shi ◽  
Ted Boden ◽  
Philippe Maillot ◽  
Larry Larson
Keyword(s):  
Sheet Resistance ◽  
Room Temperature ◽  
Strong Dependence ◽  
Amorphous Layer ◽  
High Flux ◽  
Dislocation Loops ◽  
Layer Formation ◽  
Cross Sectional ◽  
Implantation Temperature ◽  
Beam Currents

ABSTRACTWe implanted <100> silicon 200mm wafers with 20keV 11B+ to a fluence of 5×1015 atoms/ cm2 using beam currents from 1-7mA, which produced flux of about 50-350µA/cm2. The implant temperature of all wafers rose no more than five degrees above room temperature, regardless of flux. Cross sectional TEM images (as-implanted) of the highest flux samples revealed a continuous amorphous layer from the implanted surface to a depth of about 530Å. The high flux and <30°C implantation temperature allowed amorphous layer formation even with this moderate boron fluence, as was suggested by Jones, et.al.1. We observed a strong dependence of as-implanted damage on boron flux, as previously reported by Eisen and Welch2. After 900°C, 20 sec RTA, the highest flux samples had 50% lower sheet resistance than the lowest flux samples, due to better activation, as observed in SRP. When a 1050°C, 15 sec RTA was employed, this sheet resistance and activation dependence on flux disappeared. Cross sectional TEM images revealed that the size and number of the Type II end of range defects , which were centered near the amorphous and crystalline as-implanted interface, in the highest flux samples were smaller than the Type 1 dislocation loops centered about the peak disorder in the lowest flux samples after RTA. SIMS and SRP profiles indicated that transient enhanced diffusion during the 900°C, 20 sec RTA may have been reduced in the highest flux samples. Based on these observations and on previous reports, we conclude that sufficiently high flux during room temperature boron implantation will produce a continuous amorphous layer with doses that are appropriate for p-type source/drain formation. The amorphous layer will produce improved activation and damage annealing behavior in subsequent RTA, particularly as the RTA temperature is reduced.

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