Defect Evolution from Low Energy, Amorphizing, Germanium Implants on Silicon

2001 ◽  
Vol 669 ◽  
Author(s):  
Andres F. Gutierrez ◽  
Kevin S. Jones ◽  
Daniel F. Downey
Keyword(s):  
Time Window ◽  
Low Energy ◽  
Dislocation Loops ◽  
Medium Energy ◽  
Evolutionary Pathway ◽  
Plan View ◽  
Enhanced Diffusion ◽  
Conventional Furnace ◽  
Transmission Electron ◽  
Defect Evolution

ABSTRACTPlan-view transmission electron microscopy (PTEM) was used to characterize defect evolution upon annealing of low-to-medium energy, 5-30 keV, germanium implants into silicon. The implant dose was 1 × 1015 ions/cm2, sufficient for surface amorphization. Annealing of the samples was done at 750 °C in nitrogen ambient by both rapid thermal annealing (RTA) and conventional furnace, and the time was varied from 10 seconds to 360 minutes. Results indicate that as the energy drops from 30 keV to 5 keV, an alternate path of excess interstitials evolution may exist. For higher implant energies, the interstitials evolve from clusters to {311}'s to loops as has been previously reported. However, as the energy drops to 5 keV, the interstitials evolve from clusters to small, unstable dislocation loops which dissolve and disappear within a narrow time window, with no {311}'s forming. These results imply there is an alternate evolutionary pathway for {311} dissolution during transient enhanced diffusion (TED) for these ultra-low energy implants.

Study of the Effects of a Two-Step Anneal on the End of Range Defects in Silicon

2002 ◽  
Vol 717 ◽  
Author(s):  
Renata A. Camillo-Castillo ◽  
Kevin. S. Jones ◽  
Mark E. Law ◽  
Leonard M. Rubin
Keyword(s):  
Defect Density ◽  
Low Energy ◽  
Extended Defects ◽  
Dislocation Loops ◽  
Extended Defect ◽  
Enhanced Diffusion ◽  
Interstitial Concentration ◽  
Transmission Electron ◽  
Concentration Peak ◽  
Scale Down

AbstractTransient enhanced diffusion (TED) is a challenge that the semi-conductor industry has been faced with for more than two decades. Numerous investigations have been conducted to better understand the mechanisms that govern this phenomenon, so that scale down can be acheived. {311} type defects and dislocation loops are known interstitial sources that drive TED and dopants such as B utilize these interstitials to diffuse throughout the Si lattice. It has been reported that a two-step anneal on Ge preamorphized Si with ultra-low energy B implants has resulted in shallower junction depths. This study examines whether the pre-anneal step has a measurable effect on the end of range defects. Si wafers were preamorphized with Ge at 10, 12, 15, 20 and 30keV at a dose of 1x1015cm-2 and subsequently implanted with 1x1015cm-2 1keV B. Furnace anneals were performed at 450, 550, 650 and 750°C; the samples were then subjected to a spike RTA at 950°C. The implant damage was analyzed using Quantitative Transmission Electron Microscopy (QTEM). At the low energy Ge preamorphization, little damage is observed. However at the higher energies the microstructure is populated with extended defects. The defects evolve into elongated loops as the preanneal temperature increases. Both the extended defect density and the trapped interstitial concentration peak at a preanneal temperature of 550°C, suggesting that this may be an optimal condition for trapping interstitials.

Effect of Implant Energy on Silicon Defect Evolution

1997 ◽  
Vol 469 ◽  
Author(s):  
J. Desroches ◽  
V. Krishnamoorthy ◽  
K. S. Jones ◽  
C. Jasper
Keyword(s):  
Activation Energy ◽  
Primary Source ◽  
Extended Defects ◽  
Dislocation Loops ◽  
Dose Ratio ◽  
Cross Sectional ◽  
Plan View ◽  
Enhanced Diffusion ◽  
Defect Evolution ◽  
The Relationship

ABSTRACTRecent studies on the relationship between defect evolution and transient enhanced diffusion (TED) have lead to the discovery that, for sub-amorphous Si+ implants, atoms released by extended defects (i.e. {311}'s) are a primary source of interstitials for TED. In this paper, the effect of implant energy on the interstitials stored in {311} defects is reported. Silicon wafers were implanted with Si+ at fluences of 1×1014/cm2 and 2×1014/cm2 and energies of 30, 50 and 100 keV. Rapid thermal anneals (RTA) and furnace anneals were performed at times ranging from a few minutes to several hours, at temperatures of 700°, 750° and 800°C. Cross-sectional and plan-view TEM was used to obtain microstructural information. The extended defects observed upon annealing consisted of both {311} defects and dislocation loops. It was found that the ratio of the interstitials bound by extended defects and the implant dose was 0.3. Changing the implant energy did not change the total number of interstitials trapped in both types of defects combined. There was a noticeable variation in the type of defect that dominated each implant regime, despite the constant value of the trapped interstitial to dose ratio. For an RTA of 5 min. at 750°C, the ratio of {311} “rod-like” defects to dislocation loops in the 2×1014/cm2 sample unexpectedly increased as the energy increased from 30 to 50 keV.Longer furnace anneals were employed to determine the activation energy of {311} dissolution. Our data suggests a slightly higher activation energy for {311} dissolution of approximately 4.2 eV versus the previously reported 3.6 eV, however, this difference may be within experimental error.

Point Defect Detector Studies of Oxidized Silicon

1991 ◽  
Vol 238 ◽  
Author(s):  
H. L. Meng ◽  
K. S. Jones ◽  
S. Prussin
Keyword(s):  
Ion Implantation ◽  
Point Defect ◽  
Point Defects ◽  
Device Fabrication ◽  
Type Ii ◽  
Dislocation Loops ◽  
Plan View ◽  
Atom Concentration ◽  
Enhanced Diffusion ◽  
Transmission Electron

ABSTRACTIon implantation and thermal oxidation are device fabrication processes that lead to perturbation of equilibrium point defects concentration in silicon. This study investigates the interaction between oxidation-induced point defects and type II dislocation loops intentionally introduced in silicon via ion implantation. The type II dislocation loops were introduced via Si implants into (100) Si wafers at 50 keV to a dose ranging from 2×1015 to 1×1016/cm2. The subsequent furnace annealing at 900 °C was done for times between 30 min and 4 hr in either a dry oxygen or nitrogen ambient. Plan-view transmission electron microscopy (PTEM) was used to characterize the increase in atom concentration bound by dislocation loops as a result of oxidation. The results show type II dislocation loops can be used as point defect detector and they are efficient in measuring oxidation-induced point defects. It is also shown that the measured net interstitials flux trapped by dislocation loops is linearly proportional to the total supersaturation of interstitials as measured by oxidation enhanced diffusion (OED) studies.

Effects of Concurrent Co or Ti Silicidation on Transient Diffusion and End-of-Range Damage in Phosphorus Implanted Silicon

1992 ◽  
Vol 262 ◽  
Author(s):  
J.W. Honeycutt ◽  
J. Ravi ◽  
G. A. Rozgonyi
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Complete Removal ◽  
Dislocation Loops ◽  
Enhanced Diffusion ◽  
Depth Profiles ◽  
Enhanced Dissolution ◽  
Implantation Damage ◽  
Transmission Electron ◽  
Defect Behavior ◽  
Secondary Ion

ABSTRACTThe effects of Ti and Co silicidation on P+ ion implantation damage in Si have been investigated. After silicidation of unannealed 40 keV, 2×1015 cm-2 P+ implanted junctions by rapid thermal annealing at 900°C for 10–300 seconds, secondary ion mass spectrometry depth profiles of phosphorus in suicided and non-silicided junctions were compared. While non-silicided and TiSi2 suicided junctions exhibited equal amounts of transient enhanced diffusion behavior, the junction depths under COSi2 were significantly shallower. End-of-range interstitial dislocation loops in the same suicided and non-silicided junctions were studied by planview transmission electron microscopy. The loops were found to be stable after 900°C, 5 minute annealing in non-silicided material, and their formation was only slightly effected by TiSi2 or COSi2 silicidation. However, enhanced dissolution of the loops was observed under both TiSi2 and COSi2, with essentially complete removal of the defects under COSi2 after 5 minutes at 900°C. The observed diffusion and defect behavior strongly suggest that implantation damage induced excess interstitial concentrations are significantly reduced by the formation and presence of COSi2, and to a lesser extent by TiSi2. The observed time-dependent defect removal under the suicide films suggests that vacancy injection and/or interstitial absorption by the suicide film continues long after the suicide chemical reaction is complete.

Solute Segregation and Dynamics of Solid-Phase Crystallization In in and Sb-Implanted Silicon

1981 ◽  
Vol 4 ◽  
Author(s):  
J. Narayan ◽  
G. L. Olson ◽  
O. W. Holland
Keyword(s):  
Laser Power ◽  
Solid Phase ◽  
Solute Segregation ◽  
Dislocation Loops ◽  
Solid Phase Crystallization ◽  
Time Resolved ◽  
Plan View ◽  
Ion Channeling ◽  
Retrograde Solubility ◽  
Transmission Electron

ABSTRACTTime-resolved-reflectivity measurements have been combined with transmission electron microscopy (cross-section and plan-view), Rutherford backscattering and ion channeling techniques to study the details of laser induced solid phase epitaxial growth in In+ and Sb+ implanted silicon in the temperature range from 725 to 1500 °K. The details of microstructures including the formation of polycrystals, precipitates, and dislocations have been correlated with the dynamics of crystallization. There were limits to the dopant concentrations which could be incorporated into substitutional lattice sites; these concentrations exceeded retrograde solubility limits by factors up to 70 in the case of the Si-In system. The coarsening of dislocation loops and the formation of a/2<110>, 90° dislocations in the underlying dislocation-loop bands are described as a function of laser power.

Type II Dislocation Loops and their Effect on Strain in Ion Implanted Silicon as Studied by High Resolution X-ray Diffraction

1995 ◽  
Vol 378 ◽  
Author(s):  
R. H. Thompson ◽  
V. Krishnamoorthy ◽  
J. Liu ◽  
K. S. Jones
Keyword(s):  
High Resolution ◽  
Type Ii ◽  
Dislocation Loops ◽  
X Ray Diffraction ◽  
Empirical Constant ◽  
Plan View ◽  
X Ray ◽  
Transmission Electron ◽  
Measured Strain ◽  
P Type

AbstractP-type (100) silicon wafers were implanted with 28Si+ ions at an energy of 50 keV and to doses of 1 × 1015, 5 × 1015 and 1 × 1016 cm−2, respectively, and annealed in a N2 ambient at temperatures ranging from 700°C to 1000°C for times ranging from 15 minutes to 16 hours. The resulting microstructure consisted of varying distributions of Type II end of range dislocation loops. The size distribution of these loops was quantified using plan-view transmission electron microscopy and the strain arising from these loops was investigated using high resolution x-ray diffraction. The measured strain values were found to be constant in the loop coarsening regime wherein the number of atoms bound by the loops remained a constant. Therefore, an empirical constant of 7.7 × 10−12 interstitial/ppm of strain was evaluated to relate the number of interstitials bound by these dislocation loops and the strain. This value was used successfully in estimating the number of interstitials bound by loops at the various doses studied provided the annealing conditions were such that the loop microstructure was in the coarsening or dissolution regime.

Transition From Inclined to In-Plane 60° Misfit Dislocations in a Diffuse Interface

1993 ◽  
Vol 319 ◽  
Author(s):  
X. J. Ning ◽  
P. Pirouz
Keyword(s):  
Strain Relaxation ◽  
Classical Model ◽  
Diffuse Interface ◽  
Misfit Dislocations ◽  
Dislocation Loops ◽  
Boron Diffusion ◽  
Plan View ◽  
Transmission Electron ◽  
Mechanisms Of Formation ◽  
Film Substrate

AbstractDespite tremendous activity during the last few decades in the study of strain relaxation in thin films grown on substrates of a dissimilar material, there are still a number of problems which are unresolved. One of these is the nature of misfit dislocations forming at the film/substrate interface: depending on the misfit, the dislocations constituting the interfacial network have predominantly either in-plane or inclined Burgers vectors. While, the mechanisms of formation of misfit dislocations with inclined Burgers vectors are reasonably well understood, this is not the case for in-plane misfit dislocations whose formation mechanism is still controversial. In this paper, misfit dislocations generated to relax the strains caused by diffusion of boron into silicon have been investigated by plan-view and crosssectional transmission electron microscopy. The study of different stages of boron diffusion shows that, as in the classical model of Matthews, dislocation loops are initially generated at the epilayer surface. Subsequently the threading segments expand laterally and lay down a segment of misfit dislocation at the diffuse interface. The Burgers vector of the dislocation loop is inclined with respect to the interface and thus the initial misfit dislocations are not very efficient. However, as the diffusion proceeds, non-parallel dislocations interact and give rise to product segments that have parallel Burgers vectors. Based on the observations, a model is presented to elucidate the details of these interactions and the formation of more efficient misfit dislocations from the less-efficient inclined ones.

Structure Determination of Clusters Formed in Ultra-Low Energy High-Dose Implanted Silicon

2005 ◽  
Vol 108-109 ◽  
pp. 303-308 ◽  
Author(s):  
N. Cherkashin ◽  
Martin J. Hÿtch ◽  
Fuccio Cristiano ◽  
A. Claverie
Keyword(s):  
Electron Microscopy ◽  
Geometric Phase ◽  
Low Energy ◽  
High Dose ◽  
Dislocation Loops ◽  
Weak Beam ◽  
Transmission Electron ◽  
Geometric Phase Analysis

In this work, we present a detailed structural characterization of the defects formed after 0.5 keV B+ implantation into Si to a dose of 1x1015 ions/cm2 and annealed at 650°C and 750°C during different times up to 160 s. The clusters were characterized by making use of Weak Beam and High Resolution Transmission Electron Microscopy (HRTEM) imaging. They are found to be platelets of several nanometer size with (001) habit plane. Conventional TEM procedure based on defect contrast behavior was applied to determine the directions of their Burger’s vectors. Geometric Phase Analysis of HRTEM images was used to measure the displacement field around these objects and, thus, to unambiguously determine their Burger’s vectors. Finally five types of dislocation loops lying on (001) plane are marked out: with ] 001 [1/3 ≅ b and b ∝ [1 0 1], [-1 0 1], [0 1 1], [0 -1 1].

Plan-View CBED Studies of Nio-Zro2(CaO) Interfaces

1989 ◽  
Vol 159 ◽  
Author(s):  
V.P. Dravid ◽  
M.R. Notis ◽  
C.E. Lyman ◽  
A. Revcolevschi
Keyword(s):  
Electron Diffraction ◽  
Convergent Beam Electron Diffraction ◽  
Low Energy ◽  
Directionally Solidified ◽  
Plan View ◽  
Beam Electron ◽  
Transmission Electron ◽  
Interfacial Defects ◽  
Convergent Beam ◽  
Lamellar Interfaces

ABSTRACTLow energy lamellar interfaces in the directionally solidified eutectic (DSE) NiO-ZrO2(CaO) have been investigated using transmission electron diffraction and imaging. The symmetry of this bicrystal and an aspect of interfacial relaxations in the form of symmetry lowering in-plane rigid body translation (RBT) have been explored by performing convergent beam electron diffraction (CBED) experiments of plan-view bicrystals. Edge-on interfaces have also been studied by conventional and high resolution transmission electron microscopy (CTEM and HRTEM respectively), and electron diffraction fine structure analysis. Despite certain experimental difficulties due to interfacial defects and strain, plan-view CBED patterns offered valuable information concerning bicrystal symmetry and indicated no symmetry lowering RBT in this bicrystal. The suitability of plan-view CBED is briefly discussed in view of its potential as a technique to determine bicrystal symmetry and RBT.

Point Defect Detector Studies of Ge+ Implanted Silicon upon Oxidation

1992 ◽  
Vol 262 ◽  
Author(s):  
H. L. Meng ◽  
S. Prusstn ◽  
K. S. Jones
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Point Defect ◽  
Point Defects ◽  
Type Ii ◽  
Dislocation Loops ◽  
Furnace Annealing ◽  
Plan View ◽  
Atom Concentration ◽  
Transmission Electron

ABSTRACTPrevious results [1] have shown that type II (end-of-range) dislocation loops can be used as point defect detectors and are efficient in measuring oxidation induced point defects. This study investigates the interaction between oxidation-induced point defects and dislocation loops when Ge+ implantation was used to form the type II dislocation loops. The type II dislocation loops were introduced via Ge+ implants into <100> Si wafers at 100 keV to at doses ranging from 2×1015 to l×1016/cm2. The subsequent furnace annealing at 900 °C was done for times between 30 min and 4 hr in either a dry oxygen or nitrogen ambient. The change in atom concentration bound by dislocation loops as a result of oxidation was measured by plan-view transmission electron microscopy (PTEM). The results show that the oxidation rate for Ge implanted Si is similar to Si+ implanted Si. Upon oxidation a decrease in the interstitial injection was observed for the Ge implanted samples relative to the Si implanted samples. With increasing Ge+ dose the trapped atom concentration bound by the loops actually decreases upon oxidation relative to the inert ambient implying oxidation of Ge+ implanted silicon can result in either vacancy injection or the formation of an interstitial sink.

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