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Inprentus designs, manufactures, and sells custom designed mechanically-ruled blaze diffraction grating masters for use in augmented reality waveguides, synchrotron radiation facilities, spectrometer, laser and optical applications. Inprentus has developed and commercialized an innovative, dual-atomic microscope scribing technology, which is a technique for carrying out nano-scale lithography via mechanical deformation of metallic surfaces.This technology is a general purpose approach to high-precision patterning of surfaces, and is particularly suited to x-ray and EUV diffractive optics in which features must be shaped with 0.1 degree angular precision and positioned with nanometer precision over distances of tens of centimeters. Inprentus also offers comprehensive metrology services to allow for a complete characaterization of your grating. Visit www.inprentus.com for more information.
Inprentus is the world leader in mechanically-ruled blazed diffraction gratings. Inprentus was founded in 2012 to commercialize an innovative, dual atomic force microscope scribing technology, used to carry out nano-scale lithography via mechanical deformation of metallic surfaces. Inprentus designs, manufactures, and characterizes diffraction gratings for use in research facilities, manufacturing, and augmented reality. Contact Inprentus at info@inprentus.com to start your next project.
Inprentus is revolutionizing diffraction gratings! Our key offerings include:
• Variable Line Spacing (VLS); Blaze angles from 0.1° to 80°
• Echelle gratings
• Ruling on curved substrates – concave, toroidal, elliptical
• Resolving power above 100,000 (dependent on other specifications)
• High damage threshold substrates and overcoatings available
• Dimensions up to 500 x 200mm
• Line densities from 50 to 3000 l/mm
• Gold (Au) coated ruling surface with silicon or fused silica substrates
High efficiency mechanically ruled VLS blazed diffraction gratings
Simulation services for reliable predictions of in-beamline grating efficiency
Line densities at thousands of lines per millimeter
Variable line spacing (VLS)
Blaze angles as low as 0.1 degree
Large gratings up to 500 mm in length
Broad range of optics design capabilities
Diffraction gratings for beamline diagnostics
Ultra-low blaze angles for improved efficiency
Simulation services for reliable predictions of in-beamline grating efficiency
AFMs can provide fine detail on individual groove shapes and dimensions, as well as provide quantitative measurements on the high frequency roughness of a surface. While the technique can be generalized to looking at many surface properties, Inprentus has years of experience imaging thousands of gratings using in-house Nanosurf AFMs. Our metrology service leverages our experience in imaging a variety of gratings and coatings. Inprentus can provide imaging services for any grating, including blazed or binary structures, masters or replicas. Our imaging has been used on gratings of the following characteristics:
Pitch: 150 nm to 20 µm
Groove depth: < 10 nm to 4 µm
Angles*: 0.1° to > 70°
In addition to the raw scanning data, Inprentus will process the scans using our internal angle fitting software to provide statistics on the dimensions and angles for all grooves measured.
SEM uses a focused electron beam to image nanoscale features with sub-nanometer resolution. While the SEM can be used to inspect a large variety of features, Inprentus mainly focuses on imaging diffraction grating groove shapes. Groove pitch and depth dimensions are often at or below the diffraction limit, making them impossible to resolve using traditional optical metrology techniques. Groove shapes may also contain vertical sidewalls or undercut features that are difficult to access using contact or probe-based methods like AFM. A combination of FIB and SEM produces cross-sectional images of diffraction gratings allowing accurate measurement of the groove height profile. Inprentus can provide FIB/SEM imaging services for gratings having blazed, binary, and even undercut structures. Along with the raw image data, height profile images using our internal angle fitting software to provide statistics on the dimensions and angles can also be provided.
Equipment Description: Helios NanoLab 600i (SEM/FIB DualBeam)
• SEM Resolution: 0.9 nm at 15 kV
• FIB (Ga+) Resolution 4.0 nm at 1.1 pA, 30 kV
• Maximum ion beam current 65 nA (rapid ion milling)
• Platinum deposition GIS (protective layer)
• Maximum substrate size 150 mm
The defining feature of a blazed grating is the concentration of diffracted light into small patches of angle space. To measure the angular distribution of diffracted light, Inprentus uses a custom diffractometer built on a two-circle goniometer. The light source is a polarized He-Ne gas laser operating at 543 nm. Note that the source energy does not, in general, need to be at-wavelength.
The wave vectors of incoming and outgoing light can be selected independently, and the instrument can be configured to allow for pseudo-backscattering geometries. For a given surface profile (blaze), the angular distribution of 543-nm light can be rigorously calculated for each incident wave vector and compared with experiment to determine blaze fidelity. This technique thus gives the blaze and anti-blaze angle measurements at the grating level as opposed to localized measurements using techniques such as AFM or FIB/SEM.
The defining feature of a blazed grating is the concentration of diffracted light into small patches of angle space. To measure the angular distribution of diffracted light, Inprentus uses a custom diffractometer built on a two-circle goniometer. The light source is a polarized He-Ne gas laser operating at 543 nm.
Random errors in the positions of the constituent grooves, and possibly in the shapes of the grooves, produce a dim, uniform scattering background in angle space. Inprentus can configure the diffractometer to measure a normalized (with respect to blazing) straylight measurement where the diffuse background light is collected at varying wavevectors. This measurement is available in two modes:
· Angle integrated mode
· Angle resolved mode
Inprentus has commissioned a 248.6 nm reflectometer to measure efficiency of gratings used for lithography systems and DUV spectrometers. This set up consists of a NeCu pulsed laser and can make measurements in both S and P polarization. The reflectometer uses a beam splitter and two detectors to account for the shot to shot noise of the pulsed laser supply. Using a calibrated mirror as a reference, Inprentus provides absolute efficiency measurements as a service. Currently the reflectometer measurement is configured for UV wavelength but in principle can be extended to other wavelengths.
Inprentus simulation team also has the ability to compare the measurement to that of an ideal grating of perfect grooves of specified angles and pitch. We can also compare it to simulations of sampled, real groove shapes within the grating.
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