Silicide Formation By High Dose Transition Metal Implants Into Si.

1985 ◽  
Vol 51 ◽  
Author(s):  
F. H. Sanchez ◽  
F. Namavar ◽  
J. I. Budnick ◽  
A. Fasihudin ◽  
H. C. Hayden

ABSTRACTWe report preliminary results of a study on silicide formation by means of high dose transition metal implants into Si (100) single crystals.100 keV Cr+, Fe+, Co+ and Ni+ were implanted at room temperature. For the Cr+, Fe+ and Ni+ implants, no silicide formation was observed after implantation. However, both Rutherford Backscattering Spectrometry (RBS) and X-Ray Diffraction (XRD) results clearly indicated the existence of CrSi2 after the Cr-Si samples were annealed 4 hours at 550°C. In the case of the Fe+ and Ni+ implants, FeSi2 and NiSi2 were identified by XRD after annealing the implanted samples half an hour at 400°C. A layer of CoSi of about 1000 Å was observed in the as implanted Co-Si samples by both RBS and XRD.Ni+ ions accelerated to 150 keV were implanted at 350°C. A much broader distribution and higher retention of Ni was obtained in this case, showing evidence of long range atomic diffusion. NiSi and polycrystalline silicon were observed by XRD in the as implanted samples.The possibility of high dose ion implantation as a suitable technique for producing transition metal silicides is discussed.

1991 ◽  
Vol 235 ◽  
Author(s):  
Z. Tan ◽  
F. Namavar ◽  
S. M. Heald ◽  
J. I. Budnick ◽  
F. H. Sanchez

ABSTRACTWe have studied the silicide formation in Fe-implanted Si(100), with 1×1017-1×1018 Fe/cm2, using extended x-ray-absorption fine structure (EXAFS), x-ray diffraction and Rutherford backscattering spectrometry (RBS) methods. In the samples as-implanted at 350 °C, no silicide was observed at doses below 3×1017 Fe/cm2. At 5×1017 Fe/cm2, both α-FeSi2 and (β-FeSi2 form but α-FeSi2 appears to be the majority phase. As the dose increases to 7×1017 and above, ordered FeSi forms, but implantation damage is severe and a large number of Fe atoms are in very disordered environments. In addition to FeSi, Fe5Si3 was also observed in the 1×1018 Fe/cm2 sample. Upon post-implantation annealing at 700 °C or 900 °C, single phase P-FeSi2 was obtained independent of the dosage.


1992 ◽  
Vol 15 (1) ◽  
pp. 9-26 ◽  
Author(s):  
C. Nobili ◽  
F. Nava ◽  
G. Ottaviani ◽  
M. Costato ◽  
G. De Santi ◽  
...  

In-situ resistivity vs. temperature, Rutherford backscattering spectrometry, Auger electron spectroscopy and X-ray diffraction measurements have been performed in order to study the effects arising from the presence of oxygen in the annealing ambient on the integrity of amorphous films of TiSix, with x ranging from 1.45 to 2.1. Crystalisation occurs around 400 C. The presence of oxygen produces the formation of silicon and titanium oxide around 500 C. Critical analysis of the experimental results have indicated that metal oxidation is inhibited when an excess of silicon is present, which suggests the use of a sputtered Si coating cap as a medium capable of effectively decoupling the silicide film from oxygen. This avoids unwanted Ti oxidation even in heavily oxygen contaminated ambients up to the highest temperatures used for the formation of low resistivity titanium disilicide.


1994 ◽  
Vol 344 ◽  
Author(s):  
P. H. Bolt ◽  
M. E. Van Ipenburg ◽  
J. W. Geus ◽  
F. H. P. M. Habraken

AbstractAn important cause of deactivation of alumina supported transition metal (oxide) catalysts is a solid state reaction between the active component and the support. We therefore studied the hightemperature behavior of Me layers (Me = Co, Ni, Cu and Fe) on polycrystalline α-A12O3 and γ- Al2O3 substrates. The samples were first oxidized at moderate temperatures and then annealed at high temperatures (up to 1000 °C) in O2, N2, or N2/O2 mixtures. The interfacial reaction to MeA12O4 was assessed using Rutherford Backscattering Spectrometry and X-ray diffraction. The reaction rate strongly depends on the transition metal element Me: Fe < Ni < Co < Cu. Low oxygen pressures favour spinel formation. γ-A12O3 shows a much higher reactivity towards the MeOx overlayers than α-Al2O3.


1988 ◽  
Vol 143 ◽  
Author(s):  
Z. Tan ◽  
J. I. Budnick ◽  
F. Sanchez ◽  
G. Tourillon ◽  
F. Namavar ◽  
...  

AbstractThe early stages of cobalt silicide formation in high dose (1.0 to 8.0× 1017Co/cm2) cobalt implanted Si(100) are studied by extended X-ray absorption fine structure (EXAFS), X-ray diffraction (XRD) and Rutherford backscattering spectroscopy (RBS). Locally ordered silicide that is not detectable in XRD has been observed with EXAFS in the as-implanted samples. Long-range ordered phases are observed in the 3 × 1017Co/cm2 samples. After thermal annealing at 700–750°C, single phase CoSi2 with (400) orientation is formed in all implants.


1994 ◽  
Vol 354 ◽  
Author(s):  
Hannes Weishart ◽  
J. Schöneich ◽  
H. J. Steffen ◽  
W. Matz ◽  
W. Skorupa

AbstractWe studied high-dose implantation of tungsten into 6H-silicon carbide in order to synthesize a highly conductive surface layer. Implantation was performed at 200 keV at room temperature. Subsequently, the samples were annealed in two steps at 500°C and 700°C or 950°C, respectively. The influence of dose and annealing temperature on the reaction of W with SiC was investigated. Rutherford Backscattering Spectrometry (RBS), X-Ray Diffraction (XRD) and Auger Electron Spectroscopy (AES) contributed to study structure and composition of the layer as well as chemical states of the elements. During implantation sputtering became significant at a dose exceeding 1.0×1017 W+cm−2. Formation of tungsten carbide and suicide was observed already in the as-implanted state. An annealing temperature of 950°C was necessary to crystallize tungsten carbide. However, tungsten suicide remained amorphous at this temperature. Therefore, a mixture of polycrystalline tungsten carbide and amorphous tungsten suicide evolved under these conditions. The resistivity of such a layer implanted with 1.0×1017 W+ cm−2 and annealed at 950°C is 565 μΩcm.


1981 ◽  
Vol 46 (10) ◽  
pp. 2345-2353 ◽  
Author(s):  
Karel Baše ◽  
Bohumil Štíbr ◽  
Jiří Dolanský ◽  
Josef Duben

The 6-N(CH3)3-6-CB9H11 carbaborane reacts with sodium in liquid ammonia with the formation of 6-CB9H12- which was used as a starting compound for preparing the 4-CB8H14, 9-L-6-CB9H13 (L = (CH3)2S, CH3CN and P(C6H5)3), 1-(η5-C5H5)-1,2-FeCB9H10-, and 2,3-(η5-C5H5)2-2,31-Co2CB9H10- carboranes. The 4-CB8H14 compound was dehydrogenated at 623 K to give 4-(7)-CB8H12 carborane. Base degradation of 6-N(CH3)3-6-CB9H11 in methanol resulted in the formation of 3,4-μ-N(CH3)3CH-B5H10. The structure of all compounds was proposed on the basis of their 11B and 1H NMR spectra and X-ray diffraction was used in the case of the transition metal complexes.


2000 ◽  
Vol 5 (S1) ◽  
pp. 412-424
Author(s):  
Jung Han ◽  
Jeffrey J. Figiel ◽  
Gary A. Petersen ◽  
Samuel M. Myers ◽  
Mary H. Crawford ◽  
...  

We report the growth and characterization of quaternary AlGaInN. A combination of photoluminescence (PL), high-resolution x-ray diffraction (XRD), and Rutherford backscattering spectrometry (RBS) characterizations enables us to explore the contours of constant- PL peak energy and lattice parameter as functions of the quaternary compositions. The observation of room temperature PL emission at 351nm (with 20% Al and 5% In) renders initial evidence that the quaternary could be used to provide confinement for GaInN (and possibly GaN). AlGaInN/GaInN MQW heterostructures have been grown; both XRD and PL measurements suggest the possibility of incorporating this quaternary into optoelectronic devices.


2008 ◽  
Vol 595-598 ◽  
pp. 897-905
Author(s):  
Eric Caudron ◽  
Régis Cueff ◽  
Christophe Issartel ◽  
N. Karimi ◽  
Frédéric Riffard ◽  
...  

Manganese addition and subsequent yttrium implantation effects on extra low carbon steel were studied by Rutherford Backscattering Spectrometry (RBS), Reflection High Energy Electron Diffraction (RHEED), X-ray Diffraction (XRD) and Glancing Angle X-ray Diffraction (GAXRD). Thermogravimetry and in situ X-Ray Diffraction at 700°C and PO2=0.04 Pa for 24h were used to determine the manganese alloying addition and subsequent yttrium implantation effects on reference steel oxidation resistance at high temperatures. This study clearly shows the combined effect of manganese alloying addition and subsequent yttrium implantation which promotes the formation of several yttrium mixed oxides seem to be responsible for the improved reference steel oxidation resistance at high temperatures.


Sign in / Sign up

Export Citation Format

Share Document