title: A platform to parallelize planar surfaces and control their spatial separation with nanometer resolution.
abstract: Parallelizing planar surfaces and manipulating them into close proximity with spatial separation of nanoscale dimensions is critical for probing phenomena such as near-field radiative heat transport and Casimir forces. Here, we report on a novel platform, with an integrated reflected light microscope, that is capable of parallelizing two planar surfaces such that the angular deviation is <6 μrad, while simultaneously allowing control of the gap from 15 μm down to contact with ∼0.15 nm resolution. The capabilities of this platform were verified by using two custom-fabricated micro-devices with planar surfaces, 60 × 60 μm(2) each, whose flatness and surface roughness were experimentally quantified. We first parallelized the two micro-devices by using the developed platform in conjunction with a simple optical approach that relies on the shallow depth of field (∼2 μm) of a long working distance microscope objective. Subsequently, we experimentally tested the parallelism achieved via the optical alignment procedure by taking advantage of electrodes integrated into the micro-devices. Our measurements unambiguously show that the simple depth-of-field based optical approach enables parallelization such that the angular deviation between the two surfaces is within ∼500 μrad. This ensures that the separation between any two corresponding points on the parallel surfaces deviate by ∼30 nm or less from the expected value. Further, we show that improved parallelization can be achieved using the integrated micro-electrodes which enable surface roughness limited parallelization with deviations of ∼5 nm from parallelism.
authors.affiliation: Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Ganjeh
authors.forename: B
authors.initials: B
authors.lastname: Song
authors.forename: K
authors.initials: K
authors.lastname: Pagadala
authors.forename: K
authors.initials: K
authors.lastname: Kim
authors.forename: S
authors.initials: S
authors.lastname: Sadat
authors.forename: W
authors.initials: W
authors.lastname: Jeong
authors.forename: K
authors.initials: K
authors.lastname: Kurabayashi
authors.forename: E
authors.initials: E
authors.lastname: Meyhofer
authors.forename: P
authors.initials: P
authors.lastname: Reddy