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

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

1993 ◽  
Vol 303 ◽  
Author(s):  
H. Kinoshita ◽  
T. H. Huang ◽  
D. L. Kwong ◽  
P. E. Bakeman

ABSTRACTThe effect of fluorine preamorphization on boron diffusion and activation during rapid thermal annealing (RTA) has been investigated. Compared with low energy B or BF2 implant into crystalline Si, F preamorphization suppressed the transient enhanced diffusion of B and increased dopant activation. Results show that the tail diffusion was absent, and thus the junction depth of the RTA annealed sample was established by the as-implanted B profile. Secondary ion mass spectroscopy and cross-sectional transmission electron micrograph results show F accumulation near the surface and at end-of-range defects. The interaction of F with defects is believed to reduce the B diffusion during RTA.


1989 ◽  
Vol 147 ◽  
Author(s):  
K. S. Jones ◽  
J. Yu ◽  
P. D. Lowen ◽  
D. Kisker

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.


1985 ◽  
Vol 52 ◽  
Author(s):  
Muhammad Z. Numan ◽  
Z. H. Lu ◽  
W. K. Chu ◽  
D. Fathy ◽  
J. J. Wortman

ABSTRACTDeactivation of ion implanted and rapid thermal annealed (RTA) metastable arsenic in silicon during subsequent furnace annealing has been studied by sheet resistance measurement, Rutherford backs cat t ering/ channeling (RBS), and transmission electron microscopy (TEM). Following RTA, thermal annealing induces deactivation of the dopant which increases the sheet resistivity monotonically with temperature for a very short time, Dislocation loops are formed near the peak of As concentration at post-anneal temperatures of 750°C or higher, where deactivation rate is fast. At lower temperatures deactivation is accompanied by displacement of As atoms, possibly forming clusters.


2010 ◽  
Vol 1245 ◽  
Author(s):  
Terry L. Alford ◽  
Karthik Sivaramakrishnan ◽  
Anil Indluru ◽  
Iftikhar Ahmad ◽  
Bob Hubbard ◽  
...  

AbstractVariable frequency microwaves (VFM) and rapid thermal annealing (RTA) were used to activate ion implanted dopants and re-grow implant-damaged silicon. Four-point-probe measurements were used to determine the extent of dopant activation and revealed comparable resistivities for 30 seconds of RTA annealing at 900 °C and 6-9 minutes of VFM annealing at 540 °C. Ion channeling analysis spectra revealed that microwave heating removes the Si damage that results from arsenic ion implantation to an extent comparable to RTA. Cross-section transmission electron microscopy demonstrates that the silicon lattice regains nearly all of its crystallinity after microwave processing of arsenic implanted silicon. Secondary ion mass spectroscopy reveals limited diffusion of dopants in VFM processed samples when compared to rapid thermal annealing. Our results establish that VFM is an effective means of low-temperature dopant activation in ion-implanted Si.


1983 ◽  
Vol 23 ◽  
Author(s):  
W. Maszara ◽  
C. Carter ◽  
D. K. Sadana ◽  
J. Liu ◽  
V. Ozguz ◽  
...  

ABSTRACTLow energy, shallow BF2+ implants were carried out at room or liquid nitrogen temperature into deep pre-amorphized (100) Si for better control of the dopant profile and post-annealing structural defects. Cross sectional and angle polished plan view transmission electron microscopy were used to study the structural quality of the implanted layer, while SIMS provided a chemical profile. Four types of structural defects were observed in BF2+ implanted, pre-amorphized samples following rapid thermal annealing with a halogen lamp. An in-situ ion beam annealing and the presence of F in the Si lattice were related to the creation of the defects. Good correlations between F gettering and TEM observed defects were found to exist. Implantation of B+ into a pre-amorphized Si surface and subsequent rapid thermal annealing was found to produce a wide defect-free surface layer.


1989 ◽  
Vol 146 ◽  
Author(s):  
E.J. Yun ◽  
H.G. Chun ◽  
K. Jung ◽  
D.L. Kwong ◽  
S. Lee

ABSTRACTIn this paper, the interactions of sputter-deposited Ti on SiO2 substrates during rapid thermal annealing in nitrogen at 550°C - 900°C for 10 - 60 s have been systematically studied using X-ray diffraction, Auger electron spectroscopy, transmission electron diffraction, TEM & cross-sectional TEM, and sheet resistance measurements.


2002 ◽  
Vol 719 ◽  
Author(s):  
Changlong Liu ◽  
R. Delamare ◽  
E. Ntsoenzok ◽  
G. Regula ◽  
B. Pichaud ◽  
...  

Abstract(111) oriented silicon samples were implanted at room temperature with 1.55 MeV 3He ions in the dose range of 5×1015 to 5×1016/cm2. Cross-sectional transmission electron microscopy (XTEM) was used to study the evolution of bubbles and extended defects during subsequent thermal annealing at 800°C and 900°C for 30min. The He desorption from bubbles and bubble precursors was measured by means of nuclear reaction analysis (NRA). TEM observations show that no bubbles were observed in Si implanted at doses lower than 1×1016/cm2, while a well-defined cavity band was formed after implantation at 5×1016/cm2 and subsequent thermal annealing. At the intermediary dose of 2×1016/cm2, however, the evolution of bubbles and extended defects is quite different. The bubbles prefer to nucleate in large planar clusters surrounded by a high density of dislocation loops emerging from them. The clusters of bubbles act as the sources of the dislocation loops. NRA measurements indicate that the He desorption behavior is also dose-dependent. The He desorption is achieved much faster in low dose implanted Si. The results are qualitatively discussed.


1983 ◽  
Vol 23 ◽  
Author(s):  
D.K. Sadana ◽  
E. Myers ◽  
J. Liu ◽  
T. Finstad ◽  
G.A. Rozgonyi

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.


1984 ◽  
Vol 35 ◽  
Author(s):  
A M Hodge ◽  
A G Cullis ◽  
N G Chew

ABSTRACTSolid phase epitaxial regrowth of silicon on sapphire is used to improve the quality of as-received silicon films prior to conventional device processing. It has been shown that this is necessary, especially for layers of 0.3μm and thinner, if the full potential of this particular silicon on insulator technology is to be realised. Si+ ions are implanted at an energy and dose such that all but the surface of the silicon film is rendered amorphous. In this study, the layer is regrown using a rapid thermal annealer operated in the multi-second regime. A second shallower implant followed by rapid thermal annealing produces a further improvement. Characterisation of the material has been principally by cross-sectional transmission electron microscopy. The structures observed after different implant and regrowth treatments are discussed.


1991 ◽  
Vol 224 ◽  
Author(s):  
S. Batra ◽  
K. Park ◽  
S. Banerjee ◽  
T. Smith ◽  
B. Mulvaney

AbstractLateral non-uniformities can be expected in the dopant diffusion front in the substrate in polysilicon-on-single crystal Si systems upon Rapid Thermal Annealing (RTA), because the grain boundaries in polysilicon act as fast diffusant pipelines and also possibly inject defects into the substrate, which can locally enhance diffusivities in the substrate due to dopant-point defect interactions. The lateral uniformity of As, B and P ultra-shallow junctions formed in the substrate by indiffusion from as-deposited amorphous or polysilicon films has been studied using concentration dependent etching and transmission electron microscopy. Due to a larger final grain size after annealing in the case of as-deposited amorphous Si films compared to asdeposited polysilicon films, there is significant lateral doping inhomogeneities in the diffusion front. However, the doping inhomogeneities are gradually smeared out as the impurities diffuse deeper into the substrate due to lateral as well as vertical diffusion.


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