Effect of O2 Partial Pressure on Post Annealed Ba2YCU3O7-δ Thin Films

1992 ◽  
Vol 275 ◽  
Author(s):  
Julia M. PhUlips ◽  
M. P. Siegal ◽  
S. Y. Hou ◽  
T. H. Tiefel ◽  
J. H. Marshall
Keyword(s):  
Partial Pressure ◽  
Film Growth ◽  
Epitaxial Films ◽  
Pinning Force ◽  
Low Oxygen ◽  
O2 Partial Pressure ◽  
Growth Method ◽  
Lower Temperature ◽  
The Relationship

ABSTRACTEpitaxial films of Ba2YCu3O7-δ (BYCO) as thin as 250 å A and with Jc's approaching those of the best in situ grown films can be formed by co-evaporating BaF2, Y, and Cu followed by a two-stage anneal. These results extend the work on films > 2000 Å thick by R. Feenstra et al. [J. Appl. Phys. 69, 6569 (1991)]. High quality films of these thicknesses become possible if low oxygen partial pressure [p(O2) = 4.3 Torr] is used during the high temperature portion cf the anneal (Ta). The BYCO melt line is the upper limit for Ta. The use of low p(O2) shifts the window for stable BYCO film growth to lower temperature, which allows the formation of smooth films with greater microstructural disorder than is found in films grown in p(O2) = 740 Torr at higher Ta. The best films annealed in p(O2)=4.3 Torr have Jc values a factor of four higher than do comparable films annealed in P2=740 Torr. The relationship between the T required to grow films with the strongest pinning force and p(O2) is log independent of growth method (in situ or situ) over a range of five orders of magnitude of P(O2).

Growth and characterization of Ba2YCu3O7−δ films in reduced oxygen partial pressures using the BaF2 post-annealing process

1992 ◽  
Vol 7 (10) ◽  
pp. 2658-2666 ◽  
Author(s):  
M.P. Siegal ◽  
S.Y. Hou ◽  
Julia M. Phillips ◽  
T.H. Tiefel ◽  
J.H. Marshall
Keyword(s):  
Film Growth ◽  
Ex Situ ◽  
Pinning Force ◽  
Low Oxygen ◽  
Lower Growth ◽  
Partial Pressures ◽  
Growth Method ◽  
Lower Temperature

Epitaxial films of Ba2YCu3O7−δ (BYCO), as thin as 250 Å and with Jc's approaching those for the best in situ grown films, can be formed by coevaporating BaF2, Y, and Cu followed by a two-stage anneal. These results extend the work of R. Feenstra et al. [J. Appl. Phys. 69, 6569 (1991)] for film thicknesses >2000 Å. This involves using low oxygen partial pressure [p(O2) = 4.3 Torr] during the high temperature portion of the anneal, which we vary from Ta = 600 to 950 °C. The BYCO melt line is seen to be the upper limit for Ta. The use of lower p(O2) shifts the window for stable BYCO film growth to lower temperature. The lower growth temperature required for the low p(O2) process allows the formation of smooth films with greater microstructural disorder than for films grown in p(O2) = 740 Torr at higher Ta, resulting in higher Jc values by a factor of four. The relationship between the Ta required to grow films with the strongest pinning force and p(O2) is log [p(O2)] ∝ Ta−1, independent of growth method (in situ or ex situ) over a range of five orders of magnitude in p(O2).

Low-Temperature Epitaxial Growth of IN-Situ HeavilY B-Doped Si1-xGex, Films Using Ultraclean LPCVD

1998 ◽  
Vol 533 ◽  
Author(s):  
A. Morrya ◽  
M. Sakuraba ◽  
T. Matsuura ◽  
J. Murota ◽  
I. Kawashima ◽  
...  
Keyword(s):  
Low Temperature ◽  
Partial Pressure ◽  
Epitaxial Growth ◽  
Lattice Constant ◽  
Deposition Rate ◽  
Epitaxial Films ◽  
Similar Degree ◽  
Gas Mixture ◽  
Heavy Doping

AbstractIn-situ heavy doping of B into Si1-xGex epitaxial films on the Si(100) substrate have been investigated at 550°C in a SiH4(6.0Pa)-GeH4(0.1−6.0Pa)-B2H6(1.25 ×10−5−3.75 × 10−2Pa)-H2(17–24Pa) gas mixture by using an ultraclean hot-wall low-pressure CVD system. The deposition rate increased with increasing GeH4 partial pressure, and it decreased with increasing B2H6 partial pressure only at the higher GeH4 partial pressure. As the B2H6 partial pressure increased, the Ge fraction scarcely changed although the lattice constant of the film decreased. These characteristics can be explained by the suppression of both the SiH4 and GeH4 adsorption/reactions in a similar degree due to B2H6 adsorption on the Si-Ge and/or Ge-Ge bond sites. The B concentration in the film increased proportionally up to 1022cm3 with increasing B2H6 partial pressure.

In Situ Deposition of YBCO Thin Films by Sputtering under Low Oxygen Partial Pressure

1994 ◽  
Vol 33 (Part 2, No. 5B) ◽  
pp. L718-L721 ◽  
Author(s):  
Yong Ki Park ◽  
Keunseop Park ◽  
Soon-Gul Lee ◽  
Dong Chan Shin ◽  
Jong-Chul Park
Keyword(s):  
Thin Films ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Low Oxygen ◽  
Ybco Thin Films ◽  
In Situ Deposition

Oxygen potentials of PuO2-x

2012 ◽  
Vol 1444 ◽  
Author(s):  
Akira Komeno ◽  
Masato Kato ◽  
Shun Hirooka ◽  
Takeo Sunaoshi
Keyword(s):  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Measurement Data ◽  
Approximate Equation ◽  
Defect Chemistry ◽  
Thermo Gravimetry ◽  
Metal Ratio ◽  
The Relationship

ABSTRACTOxygen potentials of PuO2-x were measured at temperatures of 1473 - 1873 K by thermo-gravimetry. The oxygen potentials were determined by in situ analysis as functions of oxygen-to-metal ratio and temperature. The measurement data were analyzed on the basis of defect chemistry and an approximate equation was derived to represent the relationship among temperature, oxygen partial pressure, and deviation x in PuO2-x.

Epitaxial Film Growth of Single Crystal Ce/V Prepared by Molecular-Beam Epitaxy

1986 ◽  
Vol 77 ◽  
Author(s):  
Hitoshi Homma ◽  
Kai-Y. Yang ◽  
Ivan K. Schuller
Keyword(s):  
Single Crystal ◽  
Film Growth ◽  
High Energy ◽  
Epitaxial Films ◽  
X Ray ◽  
X Ray Scattering ◽  
Crystal Film ◽  
Epitaxial Film Growth ◽  
First Time

ABSTRACTThe growth of epitaxial films of cerium (Ce)/vanadium (V)/on single crystal sapphires (α-A1203) was studied by in-situ reflection high energy electron diffraction and x-ray scattering. For the first time Ce(111) single crystal film was grown on V(110)/α-A12O3 (1120) in the Frank-van der Merwe mode. A new epitaxial orientation, different from the well known Nishiyama-Wasserman or Kurdjumov-Sachs orientations is found in the present study. Subsequent V(110) layers grow epitaxially with three equivalent domains.

Effect of hypoxia and CO on a cytochrome P-450-mediated reaction in rabbit lungs

1981 ◽  
Vol 51 (6) ◽  
pp. 1635-1642 ◽  
Author(s):  
A. Knoblauch ◽  
A. Sybert ◽  
N. J. Brennan ◽  
J. T. Sylvester ◽  
G. H. Gurtner
Keyword(s):  
Partial Pressure ◽  
Reaction Rate ◽  
Component Model ◽  
High Affinity ◽  
O2 Partial Pressure ◽  
Tissue Po2 ◽  
Two Component ◽  
Carrier Molecule ◽  
The Relationship ◽  
Cytochrome P 450

Evidence indicates that the diffusion of O2 and CO in tissue may be facilitated by a carrier molecule having a P50 that approximates tissue O2 partial pressure (PO2; 1–15 Torr) and a much higher affinity for CO than for O2. To determine whether cytochrome P-450 in lung satisfies these criteria, we measured the effect of hypoxia and of CO on the rate of metabolism of the cytochrome P-450 mediated O-demethylation of p-nitroanisole in isolated perfused rabbit lungs. Metabolism was inhibited by 50% of a control at an estimated tissue PO2 fo 4 Torr (5.5 microM). When inspired CO2 was kept at 200 Torr and inspired CO partial pressure (PCO) varied an estimated tissue PCO/PO2 ratio of 0.025 reduced the reaction rate by 50% of control, but some metabolism persisted at PCO/PO2 ratios larger than one. The relationship between reaction rate and PCO/PO2 ratio could not be fit by a single value for Haldane constant for M (CO affinity/O2 affinity) but could be described with a two-component model in which metabolism was equally divided between a high-affinity cytochrome (M = 200) and a low-affinity cytochrome (M = 2). These findings suggest that cytochrome P-450 could act as a carrier for O2 and CO in tissue with low PO2's.

Influence of In-Situ Arsenic Doped Emitter Poly Process Conditions on RF-BiCMOS Device Parametrics

2008 ◽  
Vol 1108 ◽  
Author(s):  
Richard Egloff ◽  
Namwoong Paik ◽  
Susan Beckett ◽  
Daniel Codi ◽  
Jerry Mase ◽  
...  
Keyword(s):  
Film Growth ◽  
Active Surface ◽  
Diffusion Profile ◽  
Bipolar Transistors ◽  
Electrical Performance ◽  
Process Conditions ◽  
Dopant Incorporation ◽  
Active Surface Sites ◽  
The Relationship

AbstractThis paper discusses the influence of deposition conditions on in-situ As doped amorphous silicon emitter films used in NPN RF bipolar transistors. In-situ As doped amorphous and/or polysilicon layers improve electrical performance in BiCMOS devices by reducing the number of process steps and eliminating issues associated with implanted polysilicon on high aspect ratio topographies (plug effect). This study was made using a vertical furnace configuration capable of 150 wafer loads. Because adsorbed AsH3 decomposition species tightly bind to the active surface sites and inhibit the deposition rate, the process recipe is complex. Predictable bipolar parametrics require control of the As diffusion profile within the base region after activation, so a thorough understanding of emitter film growth and dopant incorporation is necessary.We describe the relationship between process conditions and recipe variants on transistor gain (Hfe), base current (Ib), and emitter resistance (Re). SIMS and in-line sheet resistivity measurements were used to monitor dopant incorporation into the emitter. This data was found to be predictive not only of the Hfe for a population, but also as an indicator of potential “renegade” Hfe behavior.

Effect of O2 partial pressure on YBa2Cu3O7−δ thin film growth by pulsed laser deposition

2003 ◽  
Vol 397 (1-2) ◽  
pp. 47-57 ◽  
Author(s):  
T. Haugan ◽  
P.N. Barnes ◽  
L. Brunke ◽  
I. Maartense ◽  
J. Murphy
Keyword(s):  
Thin Film ◽  
Partial Pressure ◽  
Pulsed Laser Deposition ◽  
Film Growth ◽  
Pulsed Laser ◽  
Thin Film Growth ◽  
Laser Deposition ◽  
O2 Partial Pressure
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