Sub-μm, planarized, Nb-AlO<i>x</i>-Nb Josephson process for 125 mm wafers developed in partnership with Si technology

Ketchen, M. B.; Pearson, D.J.; Kleinsasser, A. W.; Hu, C.‐K.; Smyth, M.; Logan, J.; Stawiasz, K.; Baran, E.; Jaso, M. A.; Ross, Tim; Petrillo, Karen; Manny, M.; Basavaiah, S.; Brodsky, S.; Kaplan, Steven B.; Gallagher, W. J.; Bhushan, M.

doi:10.1063/1.106405

Cited by 108 publications

(40 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In Fg. (4) we plot the dependence of AI, at resonance on t,+ Assuming that the maximum RF current which can be delivered to the load is IJ2 at a junction spacing of AI2 (the array impedance is matched to the 10 Q load at this frequency) we find that (2) predicts (AI,)-= 215 pA at 120 GHz. This is almost a factor of two smaller than the largest measured RF current amplitude.…”

Section: Discussionmentioning

confidence: 98%

Phase locking experiments in distributed arrays of Josephson junctions

Robertazzi

1995

IEEE Trans. Appl. Supercond.

View full text Add to dashboard Cite

Abstmct-Arrays of phase locked Josephson junctions are attractive for use as sub-mm wavelength voltage controlled oscillators for heterodyne mixers and free space radiators. We have performed phase locking experiments on 40 junction, parallel biased arrays of Josephson junctions coupled through transmission lines of varying delays. The longest junction to junction delay implemented was 5.4ps for a design frequency of 90 GHz, while the shortest was 1.45 ps, for a design frequency of 345 GHz.The resonant frequency f, of the arrays was found to be almost independent of the transmission line delay with f, scaling with the plasma frequency for arrays fabricated at critical current densities of lo3 and 4.5x103A/cm2. The data indicate that at the resonant frequency, strong phase locking is present among the junctions for junction separations significantly less than one half wavelength even in arrays many wavelengths long.

show abstract

Section: Discussionmentioning

confidence: 98%

Phase locking experiments in distributed arrays of Josephson junctions

Robertazzi

1995

IEEE Trans. Appl. Supercond.

View full text Add to dashboard Cite

show abstract

“…The thickness of Nb205 is estimated to be 20nm. The combination of dielectrics -anodized niobium plus the much thicker 300nm SiO, layer that follows -has two benefits: it is pinhole free, and the Nb,O, also seals the junctio'n mesa, reducing conduction pathways around the perimeter of the junction [8].…”

Section: Tri-layer Processingmentioning

confidence: 99%

A robust fabrication process for a refractory integrated SQUID gradiometer

Hutson

Weston

Bain

et al. 1995

IEEE Trans. Appl. Supercond.

View full text Add to dashboard Cite

We describe a process used successfully to fabricate large second-order planar gradiometers with integrated DC SQUIDS on two-inch silicon wafers. All the refractory materials (Nb, MO and SiO,) are deposited by magnetron sputtering. The Josephson junctions are based on the well-established Nb/AlOx/Nb trilayer technology. All Nb layers are patterned by Reactive Ion Etching using a procedure optimized by experimental design. Since only one gradiometer can fit on a wafer, extra care had to be taken in both the design of the device and the fabrication process to ensure that the yield was high. Excellent process latitude is achieved by sufficient builtin design margins to accommodate any tolerance difficulties during fabrication.

show abstract

“…Samples in group H were fabricated at Hypres. 12 Sample P was fabricated at IBM by a planarized all-refractory technology 13 ͑PARTS͒ and sample T was fabricated at MIT Lincoln Laboratories by a selective Nb anodization process ͑SNAP͒. 14 The lattice spacing p for the arrays ranges from about 10 to 20 m.…”

Section: Methodsmentioning

confidence: 99%

Self-field effects on flux flow in two-dimensional arrays of Nb Josephson junctions

1996

View full text Add to dashboard Cite

Measurements and numerical studies of the self-induced magnetic field effects on flux flow in twodimensional arrays of niobium Josephson junctions have been performed. It was found that the flux-flow resistance becomes larger as the penetration depth of the array decreases. A phenomenological model, which agrees qualitatively with the experiments and simulations, is presented to explain the self-field effects on flux flow. Due to the smaller spatial extent of supercurrents around a vortex when self-fields are important, both the mass of the vortex and the array viscosity decrease. The decreased mass and viscosity lead to an increase in flux-flow resistance. The effects of spin-wave damping are also discussed for underdamped arrays. Measurements and simulations on the spatial dependence of flux flow indicate that more complex dynamics is involved in the flux-flow regime than a simple linear flow of the vortices.

show abstract

Sub-μm, planarized, Nb-AlOx-Nb Josephson process for 125 mm wafers developed in partnership with Si technology

Cited by 108 publications

References 12 publications

Phase locking experiments in distributed arrays of Josephson junctions

Phase locking experiments in distributed arrays of Josephson junctions

A robust fabrication process for a refractory integrated SQUID gradiometer

Self-field effects on flux flow in two-dimensional arrays of Nb Josephson junctions

Contact Info

Product

Resources

About