Spreading Resistance Profiling Study of GeSi/Si Structures by High Dose Ge Implantation into Si

1994 ◽  
Vol 354 ◽  
Author(s):  
W.Y. Cheung ◽  
S.P. Wong ◽  
I.H. Wilson ◽  
Tonghe Zhang ◽  
Paul K. Chu

AbstractHetero-structures of GeSi layers on Si have been produced by high dose Ge implantation into p-type (100) Si wafers at 150 or 300 keV at various doses. From spreading resistance profiling measurements, it is found that for samples implanted at 300 keV at a sufficiently high dose, there is an unexpected resistivity type conversion due to the Ge implantation. The depths of the n-p junction formed as-implanted can be larger than 1.5 /xm, far beyond the Ge projected range. Upon annealing, the junction position moves toward the surface and eventually stops at a depth corresponding to the thickness of the GeSi layer. However, no such n-p junction formation was observed in the spreading resistance profiles of the 150 keV implanted samples. These spreading resistance results are discussed in conjunction with results from RBS and SIMS experiments.

1993 ◽  
Vol 316 ◽  
Author(s):  
W.Y. Cheung ◽  
S.P. Wong ◽  
I.H. Wilson ◽  
T.H. Zhang

ABSTRACTHigh dose Ge implantation into p-type <100> Si wafers at 150 keV has been performed at doses of 3.6×1016, 6.7×1016 and 9.0×1016 cm-2. The Ge distribution and the crystal quality of the implanted layer before and after annealing at various temperatures have been studied by RBS and channelling experiments. It is found that for the medium and high dose samples before annealing, more than 90% of the Ge atoms are in interstitial sites and after annealing at 1000°C, more than 50% of the Ge atoms have become substitutional. The situation is better for the low dose sample where less than 70% of the Ge atoms are in interstitial sites before annealing and about 80% of them become substitutional after annealing at 1000°C. The ESR spectra of these samples are of lorentzian shape with a g-value of about 2.007 and a spin density of about 6×1016 cm-3. The ESR signals of these samples have been inferred to be mainly due to Si-dangling bonds in the GeSi alloy layer and can be eliminated by annealing at 1000°C for 10 minutes. Electrical characterization of the GeSi layer by spreading resistance profiling technique shows that the implantation damage has been extended deep into the substrate before annealing. After annealing at 1000°C, these defects are removed but the spreading resistance of the surface GeSi layer is found to remain higher than that of the substrate.


1993 ◽  
Vol 298 ◽  
Author(s):  
Ashawant Gupta ◽  
Yao-Wu Cheng ◽  
Jianmin Qiao ◽  
M. Mahmudur Rahman ◽  
Cary Y. Yang ◽  
...  

AbstractIn an attempt to substantiate our previous findings of boron deactivation and/or donor complex formation due to high-dose Ge and C implantation, SiGe and SiGeC layers were fabricated and characterized. Cross-sectional transmission electron microscopy indicated that the SiGe layer with peak Ge concentration of 5 at% was strained; whereas, for higher concentrations, stacking faults were observed from the surface to the projected range of Ge as a result of strain relaxation. Results of spreading resistance profiling were found to be consistent with the model of dopant deactivation due to Ge implantation and subsequent solid phase epitaxial growth of the amorphous layer. Furthermore, for unstrained SiGe layers (Ge peak concentration ≥7 at%), formation of donor complexes is indicated. Preliminary photoluminescence results correlate with the spreading resistance profiling results and indicate shallow donor complex formation.


1981 ◽  
Vol 4 ◽  
Author(s):  
Douglas H. Lowndes ◽  
Bernard J. Feldman

ABSTRACTIn an effort to understand the origin of defects earlier found to be present in p–n junctions formed by pulsed laser annealing (PLA) of ion implanted (II) semiconducting GaAs, photoluminescence (PL) studies have been carried out. PL spectra have been obtained at 4K, 77K and 300K, for both n–and p–type GaAs, for laser energy densities 0 ≤ El ≤ 0.6 J/cm2. It is found that PLA of crystalline (c−) GaAs alters the PL spectrum and decreases the PL intensity, corresponding to an increase in density of non-radiative recombination centers with increasing El. The variation of PL intensity with El is found to be different for n– and p–type material. No PL is observed from high dose (1 or 5×1015 ions/cm2 ) Sior Zn-implanted GaAs, either before or after laser annealing. The results suggest that the ion implantation step is primarily responsible for formation of defects associated with the loss of radiative recombination, with pulsed annealing contributing only secondarily.


1996 ◽  
Vol 438 ◽  
Author(s):  
V. Krishnamoorthy ◽  
D. Venables ◽  
K. Moeller ◽  
K. S. Jones ◽  
B. Freer

Abstract(001) CZ silicon wafers were implanted with arsenic (As+) at energies of 10–50keV to doses of 2×1014 to 5×1015/cm2. All implants were amorphizing in nature. The samples were annealed at 700°C for 16hrs. The resultant defect microstructures were analyzed by XTEM and PTEM and the As profiles were analyzed by SIMS. The As profiles showed significantly enhanced diffusion in all of the annealed specimens. The diffusion enhancement was both energy and dose dependent. The lowest dose implant/annealed samples did not show As clustering which translated to a lack of defects at the projected range. At higher doses, however, projected range defects were clearly observed, presumably due to interstitials generated during As clustering. The extent of enhancement in diffusion and its relation to the defect microstructure is explained by a combination of factors including surface recombination of point defects, As precipitation, As clustering and end of range damage.


1995 ◽  
Vol 402 ◽  
Author(s):  
G. Curello ◽  
R. Gwilliam ◽  
M. Harry ◽  
R. J. Wilson ◽  
B. J. Sealy ◽  
...  

AbstractIn this work iridium silicidation of high dose Ge+ implanted Si layers has been studied. Compositional graded SiGe layers with a Ge peak concentration between 6 at.% and 12 at.% have been fabricated using 200 keV Ge+ ion implantation into (100) Si. A 20 nm thick Ir film was then deposited by e-beam evaporation with thermal reaction being performed to both regrow the implantation damage and form the silicide. The crystal quality of the SiGe layer and its interaction with the Ir film have been studied by cross-sectional Transmission Electron Microscopy (XTEM) and Rutherford Backscattering Spectrometry (RBS).Solid Phase Epitaxial Growth (SPEG) in the low dose case has produced a defect free SiGe layer with the formation of the IrSi phase. The annealing ambient was found to be critical for the silicidation. For the high dose case, as expected, strain relaxation related defects were observed to nucleate at a depth close to the projected range of the Ge+ implant and to extend up to the surface. A second rapid thermal annealing at higher temperatures, performed in forming gas, consumed most of the defective layer moving the silicide interface closer to the peak of the Ge distribution. A second low dose Ge+ implant following the metal deposition has been found to have a beneficial effect on the quality of the final interface. An amorphizing 500 keV Si+ implant followed by SPEG has finally been used to move the end of range defects far from the interface.


2010 ◽  
Vol 25 (6) ◽  
pp. 065012 ◽  
Author(s):  
M Pociask ◽  
I I Izhnin ◽  
S A Dvoretsky ◽  
Yu G Sidorov ◽  
V S Varavin ◽  
...  

1996 ◽  
Vol 439 ◽  
Author(s):  
V. Krishnamoorthy ◽  
D. Venables ◽  
K. Moeller ◽  
K. S. Jones ◽  
B. Freer

Abstract(001) CZ silicon wafers were implanted with arsenic (As+) at energies of 10–50keV to doses of 2x 1014 to 5x1015/cm2. All implants were amorphizing in nature. The samples were annealed at 700°C for 16hrs. The resultant defect microstructures were analyzed by XTEM and PTEM and the As profiles were analyzed by SIMS. The As profiles showed significantly enhanced diffusion in all of the annealed specimens. The diffusion enhancement was both energy and dose dependent. The lowest dose implant/annealed samples did not show As clustering which translated to a lack of defects at the projected range. At higher doses, however, projected range defects were clearly observed, presumably due to interstitials generated during As clustering. The extent of enhancement in diffusion and its relation to the defect microstructure is explained by a combination of factors including surface recombination of point defects, As precipitation, As clustering and end of range damage.


1989 ◽  
Vol 147 ◽  
Author(s):  
D. L. Dugger ◽  
M. B. Stern ◽  
T. M. Rubico

AbstractThe distribution of Mg+ (a p-type dopant for GaAs) and As+ (an p-type dopant for Si) implanted into both photoresist (PR) and polyimide (PI) have been determined experimentally. Range data of Mg ions at 200 keV and 300 keV and As ions at 150 keV have been measured by Secondary Ion Mass Spectroscopy (SIMS). SIMS values for the projected range Rp and the standard deviation ARp were compared to range profile data calculated using the Projected Range Algorithm (PRAL) of Biersack [1] as well as the standard LSS theory [2]. While the values for Rp calculated from the PRAL model generally agreed within 10% of the SIMS values, the calculations underestimated Rp for PR but were in good agreement for PI. The LSS calculations underestimated Rp in both materials.


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