Quantum X align

Dip-in Laser Lithography (DiLL) is the standard printing configuration of Quantum X align. Nanoscribe invented this technology for 3D microfabrication with the highest precision and the lowest aberration on the market. In this configuration, the objective lens is immersed in the photoresin, which also serves as an optical immersion medium. The refractive index matching between the focusing optics and the print material guarantees ideal, aberration-free focusing with the highest resolution in 2PP-based 3D printing. Furthermore, the writing laser is not focused through the substrate (e.g. oil immersion configuration), but writes the print object directly onto the substrate. Consequently, the working distance of the focusing optics does not limit the height of the 3D-printed object, which is especially beneficial for printing meso- and macroscale objects.

Nanoscribe’s substrate holders guarantee a precise fixation and enable to print on the facet of single fibers, fiber arrays and photonic chips. Furthermore, standard substrates such as microscope slides and wafer formats from 1” to 6” can be easily processed. The advanced interface finder of Quantum X align includes two complementary modes for reflection and fluorescence detection of the substrate surface. In combination with the Dip-in Laser Lithography (DiLL) configuration, a wide range of reflective (e.g. silicon wafers), transparent and opaque substrates (e.g. glass and polymer substrates) can be used.

With the fiber illumination unit, the fiber core can be easily located using the Quantum X align touchscreen. First, the print field on the fiber array is defined by manual coarse alignment with a double-tap on the touchscreen. Then, Quantum X align automatically detects the position of the fibers with submicron accuracy and compensates for smallest substrate tilts during the print in all spatial directions.

For this, the autofocus routine first detects the surface of the optical fiber. Next, the system identifies the illuminated fiber core and marks the center of the core as the origin of a virtual coordinate system to which the print object is aligned. The virtual z-axis and its orientation in space is determined by moving the substrate downwards and identifying the position of the fiber core on multiple positions along this vertical movement of the stage. As a result, the optical axis orientation is detected and set as the virtual z-axis for a tilt compensated printing of microoptics with submicron precision.

To support the fiber printing process, Quantum X align is equipped with a LED fiber illumination unit. Up to 32 individual fibers with standard PC or APC connectors can be plugged into this unit. The specially designed fiber substrate holder secures single fibers or fiber arrays and can load up to four fiber arrays at a time. Once inserted into the printer, the illuminated fiber cores can be easily identified using the live microscope view on the touchscreen of Quantum X align. A double tab on the screen allows the stage to be moved to any position within the 50 x 50 mm² print area. And you can use a crosshair to roughly align the printing process to the optical fibers. Intuitive gestures on the screen let you zoom in and out to find the right position.

With the new workflow you can load multiple .stl or .obj files and merge them to one single print object. This enables to set individual print parameters, such as slicing, hatching, laser power or scan speed, for each individual part of the print object. As a result, support structures can be printed faster with coarse parameters, whereas optical most relevant parts such as the surface of a lens can be printed with finer settings that result in a surface roughness R_a of 10 nm and even less. Of course, predefined print parameters are available out of the box but can also be customized to fit your design and specific requirements. The individual parts are then merged to one print project and uploaded to Quantum X align.

Adjusting print parameters to the functional requirements of the print object saves valuable printing time and enables Quantum X align to process an 8x V-groove fiber array in less than 20 minutes.

The Quantum X align features an automatic high-precision confocal imaging module for 3D mapping of substrate topographies. This module is integrated into the beam path of the near-infrared laser. The laser beam is scanned over the sample surface and the back-scattered light is confocally detected by the system. High-resolution 3D topographies are recorded by moving the stage vertically and repeating surface scans multiple times along the z-axis. A spatial filter pinhole in front of the detector ensures that only light from the focal plane is detected, resulting in a lateral detection accuracy down to 100 nm. The 3D topographies measured with this system are more precise than image-based ones using the system camera.

The 3D alignment of the print object is based on the high-resolution 3D topography mappings by the confocal unit. For the precise alignment of optical components on a photonic chip, smart software algorithms automatically identify predefined markers and topography features. Thus, the exact position and orientation of the waveguides on the chip can be determined. A virtual coordinate system is then set to the exit of the waveguide, perfectly aligned with its optical axis and orientation. The desired optical components are printed with respect to this coordinate system, ensuring best optical performance and minimizing coupling losses. This enables efficient light coupling by Free Space Microoptical Coupling (FSMOC).

Printing onto a chip’s facet from top, i.e. perpendicular to the substrate surface, is a challenging task and requires not only a precise positioning system but also smart solutions to overcome the “shadowing effect”: When printing onto a facet, a substantial part of the intensity in the focal point of the printing laser is lost, because the light is partly blocked by the edge of the substrate. Close to the substrate wall the shadowing effect is more prominent and requires higher exposure doses.
For printing aligned onto the facet of a chip the Quantum X align uses a confocal module to detect the edge of the chip and automatically adjusts the laser power during printing with a proprietary dose compensation feature. As a result, microoptics and other print objects are printed onto the facet of a substrate with submicron accuracy.

The advanced autofocus system reliably finds the interface of any substrate with maximum accuracy and repeatable print results. Three live-view cameras facilitate process control and monitoring. An automatic dispenser applies the correct amount of photoresin onto the substrate, reducing workload and enabling remote operation. To simplify switching between hardware configurations, the Quantum X align automatically detects the printheads and substrate holders. Quantum X align software controls and monitors print jobs in real time and supports intuitive operation through an interactive touchscreen control panel, or remotely from the office via the remote access software nanoConnectX. This remote access also simplifies the work of entire user groups, e.g. members of a research group or a department, with a single or multiple systems, each of them accessing the Quantum X align from their own computer.

Quantum X align is the ideal tool for high-speed 3D microfabrication of objects with submicron feature sizes, surface roughness profiles of 5 nm and less and nanoscale alignment precision. to achieve the highest precision in 3D printing, it is essential to take certain precautions with regard to the system itself and the installation site. Quantum X align should be placed in a room with stable room temperature and humidity. The printer is equipped with a heavy granite base to reduce the influence of vibrations and temperature fluctuations of the environment. However, it is important to install the high-precision printer in a location that minimizes external vibrations. For the handling of the UV-sensitive photoresin outside the printer, we recommend equipping the room with yellow light and meeting the basic requirements of a chemistry lab to handle organic solvents for the print development process properly.

To gain an understanding of how the Quantum X align work environment can be configured, please contact us and visit our Micro Experience Center here at Nanoscribe or book your online tour.

Free Space Microoptical Coupling (FSMOC) offers a highly robust and efficient light coupling solution for photonic packaging and integration. Freeform microoptics fabricated directly on the optical interface of chips or fibers enable tailored beam shaping and mode field adjustments. This leads to relaxed alignment tolerances between optical elements and eliminates the need for active alignment, e.g. for fabricating optical interconnects. FSMOC is flexible in use and can be easily tailored to meet application specific requirements. Even previous mode field adjustments at the chip level can be transferred to the new 3D printing approach.

Advantages in a nutshell:

• Cost efficient photonics packaging strategy
• Relaxed alignment tolerances for passive alignment
• Achievable coupling losses down to ≤ 1 dB
• Easy and quick adaption to new requirements and applications

nanoPrintX is a print project development software based on scene graphs. With this modern, tree-like data structure, you can easily generate logical relationships between elements of the print and assign individual properties or print parameters. This allows you to exactly define how the printed structures are aligned to the substrate and to each other. Load multiple CAD designs into one scene and assign different print parameters to each part design. This allows you to fine-tune your print for optimized quality and speed for each section. With the combination of the new 3D printing by 2GL^® technology and the smart slicing feature with coarse speed print parameters, optical elements can be printed up to 60 times faster. Many actions can be dynamically configured using drag and drop.

The fabrication of lensed fiber arrays (LFAs) and aligned prints on optical fibers with individual designs is enabled by the precise interaction of hardware components and software. With nanoPrintX, individual Lensed Fiber Arrays (LFAs) can be designed in just a few steps: the fiber node is selected in the scene graph, and individual lens designs can be placed on the fiber as .STL or .OBJ files. Multiple copies of the same print can be easily generated, or each fiber can be customized with an individual design. The print project is then uploaded to the Quantum X aligner and can be started from the touchscreen of the machine or remotely via nanoConnectX. After a fast coarse alignment, the virtual fiber positions of the print project are matched with the detected positions, and the aligned print is started fully automatically.

The 3D slicer software usually prepares CAD designs for printing. This means CAD designs, typically created with CAD software, are loaded into the slicer software, and print parameters such as slicing and hatching distances are set for printing. However, nanoPrintX is more than a simple 3D slicer software. In addition to its alignment functionalities, nanoPrintX includes simple building blocks such as a cube, a cone, and a cylinder, which can be combined in many different ways. Furthermore, with the lens node, nanoPrintX includes a powerful parametric lens design tool. Spherical and aspherical lenses can be developed in accordance with ISO standard 10110. All parameters that describe the lens can then be transferred to nanoPrintX, which automatically renders the lens design.