Spreading of thin-film metal patterns deposited on nonplanar surfaces using a shadow mask micromachined in Si (110)

Tiggelaar, Roald M.; Berenschot, J.W.; Elwenspoek, M.; Gardeniers, Han; Dorsman, R.; Kleijn, Chris R.

doi:10.1116/1.2747629

Cited by 18 publications

(12 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(e) Typical ellipsometry spectra Psi (Ψ) and delta (Δ) measured and modeled for the PZT on Pt/glass at an incidence angle of 65°. shadow masks or differential deposition can modify the film thickness distribution, but requires custom designs for different sputtering configurations and substrates, [49][50][51][52][53][54] and can be difficult to implement. While specialized magnetron sputtering geometries would be used for adjustable x-ray optics adopted for a flight mission, initial mirror prototypes are made using angled circular off-axis planar magnetrons with rotating substrates.…”

Section: Introductionmentioning

confidence: 99%

Thickness distribution of sputtered films on curved substrates for adjustable x-ray optics

Bishop

Walker

DeRoo

et al. 2019

J. Astron. Telesc. Instrum. Syst.

View full text Add to dashboard Cite

McKinstry, "Thickness distribution of sputtered films on curved substrates for adjustable x-ray optics," J.Abstract. Piezoelectric adjustable x-ray optics use magnetron sputtered thin film coatings on both sides of a thin curved glass substrate. To produce an optic suitable for a mission requiring high-angular resolution like "Lynx," the integrated stresses (stress × thickness) of films on both sides of the optic must be approximately equal. Thus, understanding how sputtered film thickness distributions change for convex and concave curved substrates is necessary. To address this, thickness distributions of piezoelectric Pb 0.995 ðZr 0.52 Ti 0.48 Þ 0.99 Nb 0.01 O 3 films are studied on flat, convex, and concave cylindrical substrates with a 220-mm radius of curvature. A mathematical model of the film thickness distribution is derived based on the geometric properties of the sputter tool and the substrate, and film thicknesses deposited with a commercially available sputtering tool are measured with spectroscopic ellipsometry. Experiment and modeled results for flat and convex curved substrates demonstrate good agreement, with average relative thickness distribution difference of 0.19% and −0.10% respectively, and a higher average difference of 1.4% for concave substrates. The calculated relative thickness distributions are applied to the convex and concave sides of a finite-element analysis (FEA) model of an adjustable x-ray optic prototype. The FEA model shows that, left uncorrected, the relative film thickness variation will yield an optic with an optical performance of 2.6 arc sec half power diameter (HPD) at 1 keV. However, the mirror figure can be corrected to diffraction-limited performance (0.3 arc sec HPD) using the piezoelectric adjusters, suggesting that the tolerances for applying a balanced integrated stress on both sides of a mirror are alleviated for adjustable x-ray optics as compared to traditional static x-ray mirrors. Furthermore, the piezoelectric adjusters will also allow changes in mirror figure over the telescope lifetime due to drift in the stress states of the x-ray surfaces to be corrected on orbit.

show abstract

Section: Introductionmentioning

confidence: 99%

Thickness distribution of sputtered films on curved substrates for adjustable x-ray optics

Bishop

Walker

DeRoo

et al. 2019

J. Astron. Telesc. Instrum. Syst.

View full text Add to dashboard Cite

show abstract

“…This reduces the number of possible contamination sources, with the added benefit of being able to prepare and analyse the sample while maintaining ultra-high vacuum (UHV) conditions. Stencil lithography can be used in static [6][7][8][9] or dynamic mode [10][11][12][13] and is used in a variety of different applications such as magnetic nanostructures [11,[14][15][16], fabrication of in situ interconnects [17,18], molecular beam epitaxial deposition through a stencil mask [13,19] and defining clean metal patterns [5,7,8,[20][21][22]. Nanostencils are commonly fabricated by focused ion beam (FIB) techniques [4,23].…”

Section: Introductionmentioning

confidence: 99%

Effect of using stencil masks made by focused ion beam milling on permalloy (Ni₈₁Fe₁₉) nanostructures

et al. 2013

View full text Add to dashboard Cite

Focused ion beam (FIB) milling is a common fabrication technique to make nanostencil masks which has the unintended consequence of gallium ion implantation surrounding milled features in silicon nitride membranes. We observe major changes in film structure, chemical composition, and magnetic behaviour of permalloy nanostructures deposited by electron beam evaporation using silicon nitride stencil masks made by a FIB as compared to stencil masks made by regular lithography techniques. We characterize the stenciled structures and both types of masks using transmission electron microscopy, electron energy loss spectroscopy, energy dispersive x-ray spectroscopy, magnetic force microscopy and kelvin probe force microscopy. All these techniques demonstrate distinct differences at a length scale of a 1-100 nm for the structures made using stencil mask fabricated using a FIB. The origin of these differences seems to be related to the presence of implanted ions, a detailed understanding of the mechanism however remains to be developed.

show abstract

“…Shadow masks are useful for structures where no freestanding features or structures with large aspect ratios are needed [16,17]. During deposition the shadow mask can warp due to differential thermal expansion in the plasma, leading to hazy feature definition.…”

Section: Introductionmentioning

confidence: 99%

Patterning of platinum (Pt) thin films by chemical wet etching in Aqua Regia

Köllensperger

Karl

Ahmad

et al. 2012

J. Micromech. Microeng.

View full text Add to dashboard Cite

The chemical and physical properties of platinum (Pt) make it a useful material for microelectromechanical systems and microfluidic applications such as lab-on-a-chip devices. Platinum thin-films are frequently employed in applications where electrodes with high chemical stability, low electrical resistance or a high melting point are needed. Due to its chemical inertness it is however also one of the most difficult metals to pattern. The gold standard for patterning is chlorine RIE etching, a capital-intensive process not available in all labs. Here we present simple fabrication protocols for wet etching Pt thin-films in hot Aqua Regia based on sputtered Ti/Pt/Cr and Cr/Pt/Cr metal multilayers. Chromium (Cr) or titanium (Ti) is used as an adhesion layer for the Pt. Cr is used as a hard masking layer during the Pt etch as it can be easily and accurately patterned with photoresist and withstands the Aqua Regia. The Cr pattern is transferred into the Pt and the Cr mask later removed. Only standard chemicals and cleanroom equipment/tools are required. Prior to the Aqua Regia etch any surface passivation on the Pt is needs to be removed. This is usually achieved by a quick dip in dilute hydrofluoric acid (HF). HF is usually also used for wet-etching the Ti adhesion layer. We avoid the use of HF for both steps by replacing the HF-dip with an argon (Ar) plasma treatment and etching the Ti layer with a hydrogen peroxide (H 2 O 2) based etchant.

show abstract

Spreading of thin-film metal patterns deposited on nonplanar surfaces using a shadow mask micromachined in Si (110)

Abstract: Selective-area chemical-vapor deposition of Si using a bilayer dielectric mask patterned by proximal probe oxidation J.

Cited by 18 publications

References 46 publications

Thickness distribution of sputtered films on curved substrates for adjustable x-ray optics

Thickness distribution of sputtered films on curved substrates for adjustable x-ray optics

Effect of using stencil masks made by focused ion beam milling on permalloy (Ni₈₁Fe₁₉) nanostructures

Patterning of platinum (Pt) thin films by chemical wet etching in Aqua Regia

Contact Info

Product

Resources

About

Spreading of thin-film metal patterns deposited on nonplanar surfaces using a shadow mask micromachined in Si (110)

Abstract: Selective-area chemical-vapor deposition of Si using a bilayer dielectric mask patterned by proximal probe oxidation J.

Cited by 18 publications

References 46 publications

Thickness distribution of sputtered films on curved substrates for adjustable x-ray optics

Thickness distribution of sputtered films on curved substrates for adjustable x-ray optics

Effect of using stencil masks made by focused ion beam milling on permalloy (Ni81Fe19) nanostructures

Patterning of platinum (Pt) thin films by chemical wet etching in Aqua Regia

Contact Info

Product

Resources

About

Effect of using stencil masks made by focused ion beam milling on permalloy (Ni₈₁Fe₁₉) nanostructures