Quantum Dot Inkjet Printing is a core process for pixel fabrication of next-generation displays, and is widely adopted in the production of high-end display panels thanks to its high color gamut and high contrast ratio. Ink droplet volume is a critical microscale parameter that determines inkjet forming quality. The consistency and stability of single droplet volume directly affect the uniformity of pixel film thickness and quantum dot luminous efficiency, acting as a key indicator for production yield control. Minor deviations in droplet volume during mass production will cause process defects such as pixel color shift, film wrinkling and uneven luminescence. Therefore, high-precision volume detection has become an essential part of the quantum dot inkjet process.
Composed of nano-scale quantum dot particles, quantum dot ink features unique rheological properties. Its dynamic viscosity and surface tension are susceptible to driving voltage, ambient temperature and humidity, which easily lead to ejection anomalies including volume dispersion, satellite droplets and droplet interruption. Conventional 2D imaging and weighing methods suffer from limited accuracy and fail to detect picoliter-level tiny volume deviations. They cannot meet the quality control requirements of micro-nano precision processes, and may result in unqualified forming quality and fluctuating production yield in mass production.
As a high-precision micro-nano inspection instrument, the White Light Interferometer (WLI) enables non-contact and non-destructive accurate measurement of ink droplet volume based on the white light interferometry ranging principle. By acquiring the 3D micro-morphology of ink dots deposited on substrates and adopting interference fringe analysis and 3D reconstruction algorithms, it accurately calculates the 3D volume, film thickness and profile flatness of ink droplets, and efficiently identifies latent process defects such as deformed droplets and out-of-tolerance volume. With nanometer-level detection accuracy, it realizes precise calibration of standard droplet volume values and traceability of deviations.
In practical mass production quality control systems, the WLI can be used to calibrate volume parameters of RGB three-color quantum dot ink and establish standardized process thresholds. Combined with the optimization of inkjet drive waveforms and ejection parameters, it builds a closed-loop quality control system of "detection - analysis - parameter adjustment". Accurate control over ink droplet volume effectively avoids forming defects, stabilizes pixel color performance, and greatly improves the forming quality and production yield of quantum dot inkjet processes, fully meeting the precision manufacturing demands of high-end display panels.
Recrom — Professional Provider of Integrated Optical 3D Measurement Solutions
Wide-Field 3D White Light Interferometer - Full-Range Measurement Solution (For Industrial & Semiconductor Use)
Breaking the limitations of traditional measurement and setting a new paradigm for precision measurement. Leveraging core innovative technologies, the wide-field 3D white light interferometer delivers nanoscale measurement across all scenarios. Combining high efficiency and outstanding accuracy, it redefines industrial measurement standards. It provides comprehensive technical support for the inspection of semiconductors, optical components and various precision parts, meeting stringent measurement requirements across multiple industries.
Four Core Technological Innovations (Industrial Grade, Tailored for Semiconductor Scenarios)
1. Wide Field of View & High Precision, Breaking Industry Norms
It overcomes the drawbacks of traditional equipment. Objective lenses with magnification below 1× are applicable to diverse scenarios, enabling wide-field observation and high-precision measurement with a single unit.
Equipped with a brand-new lightweight 0.6× lens, it features an extra-large single frame field of view of 14 mm. Paired with a turret design compatible with four objective lenses, the instrument fully satisfies the needs for wide-field viewing and high-precision measurement. It adapts to inspection of various complex samples, eliminates frequent device switching, and significantly improves inspection efficiency and data accuracy.
(The above is the measured flatness of a 14 mm end face. It ensures precise planar accuracy of components and lays a solid foundation for subsequent measurement of semiconductor devices and precision optical parts.)
(Measured data: 6 pm = 0.006 nm. It accurately characterizes surface roughness (Ra/Rz) and meets the ultra-precision measurement requirements for semiconductor chips and ultra-precision components.)
2. 80° Tilt Measurement, Beyond Planar Measurement Limits
Dispelling the industry consensus that white light interferometry only works for planar surfaces, our advanced high-angle measurement technology enables reliable measurement on steep inclined planes and conical surfaces up to 80° with excellent compatibility. A single unit handles full-scenario measurement without extra dedicated instruments. It expands the application scope and is ideal for inspecting irregular components in semiconductor packaging, precision machining and other fields.
3. True Color 3D Metrology, Redefine User Experience
Breaking through technical bottlenecks in the industry, this system retains the capability to analyze interference fringes via monochrome CMOS while enabling RGB true color imaging. It eliminates the limitation of conventional white light interferometers that only produce monochrome images.
It clearly displays sample morphology and color details, delivering more comprehensive measurement data and intuitive analysis with higher reference value. The solution is well-suited for sophisticated applications such as surface defect detection of semiconductor devices.
4. Upper and Lower Surface Parallelism Measurement for Diverse Application Scenarios
Featuring a unique optical path design, the system can measure the thickness and upper/lower surface parallelism of opaque products. It caters to the measurement requirements of various opaque precision parts and multi-layer semiconductor devices. This function further expands the application scope, enhances equipment versatility and reduces the cost of additional equipment investment.
Friction Surface Characterization Measurement Cases (Exclusive for Industrial and Semiconductor Fields)
Comparative friction tests of different lubricantsScratch depth and wear area of friction surfaces are measured to visually distinguish the lubrication performance of various lubricants. It provides data reference for optimizing lubrication systems of industrial equipment and maintaining transmission parts of semiconductor devices.
Friction surface measurement of curved rollersDirect quantitative measurement cannot be performed on the original friction surfaces of curved rollers. After surface flattening, wear amount can be accurately measured and evaluated. This solution is applicable to quality inspection of mechanical transmission components and rollers for semiconductor equipment.
Friction surface characterization after laser drillingTexture detection is carried out on friction test surfaces post laser drilling. It enables accurate analysis of how process parameters affect the roughness and flatness of friction surfaces, and is widely used in semiconductor packaging, precision machining and other sectors.
Roughness measurement for friction surfaces of automotive and semiconductor componentsPrecise testing of roughness (Ra/Rz) is implemented on friction parts of automobiles and contact surfaces of semiconductor devices. It delivers authoritative data for component quality control and reliability verification of semiconductor products.
Recrom Optics delivers professional integrated optical 3D measurement solutions. Empowered by core technologies, we serve scenarios including precision measurement, semiconductor characterization and industrial quality inspection, helping diverse industries achieve high-quality development and product iteration and upgrading.