Wafer Thickness (THK) Geometric Measurement System

The WD4000 Wafer Thickness THK Geometric Measurement System is compatible with different materials and surface roughness levels, capable of measuring highly warped wafers, and provides more accurate data for both sides of the wafer. Through non-contact measurement, it reconstructs the three-dimensional topography of the wafer. The powerful measurement and analysis software stably calculates wafer thickness, TTV, BOW, and WARP, enabling efficient measurement while effectively preventing scratches and defects on the wafer.

The WD4000 Wafer Thickness THK Geometric Measurement System can be widely applied in substrate manufacturing, wafer fabrication, packaging process inspection, 3C electronic glass screens and their precision components, optical processing, display panels, MEMS devices, and other ultra-precision machining industries. It can measure various surfaces, from smooth to rough and low to high reflectivity, and evaluate thickness, roughness, flatness, micro-geometric profiles, curvature, and other parameters for workpieces ranging from nanometers to micrometers. It supports measurements of wafers made from materials such as gallium arsenide, gallium nitride, gallium phosphide, germanium, indium phosphide, lithium niobate, sapphire, silicon, silicon carbide, and glass.

Measurement Functions

1. Thickness Measurement Module: Thickness, TTV (Total Thickness Variation), LTV, BOW, WARP, TIR, SORI, flatness, etc.;

2. Microscopic Topography Measurement Module: Roughness, flatness, micro-geometric profiles, area, volume, etc.

3. Data Processing Functions: Provides four major modules—position adjustment, correction, filtering, and extraction. Position adjustment includes functions such as image leveling and mirroring; correction includes spatial filtering, retouching, spike denoising, etc.; filtering includes form removal, standard filtering, spectral filtering, etc.; extraction includes region extraction and profile extraction.

4. Analysis Functions: Offers five major analysis capabilities—geometric profile analysis, roughness analysis, structural analysis, frequency analysis, and functional analysis. Geometric profile analysis includes feature measurements such as step height, distance, angle, curvature, as well as straightness and roundness form tolerance evaluations; roughness analysis covers full parameters according to international standards ISO4287 (line roughness), ISO25178 (areal roughness), and ISO12781 (flatness); structural analysis includes pore volume and trough analysis.

Product Advantages

1. Non-Contact Thickness and 3D Wafer Topography Integrated Measurement

The WD4000 Wafer Thickness THK Geometric Measurement System integrates thickness measurement modules with 3D topography and roughness measurement modules, allowing a single machine to perform measurements of thickness, TTV, LTV, BOW, WARP, roughness, and 3D topography.

2. High-Precision Thickness Measurement Technology

(1) Utilizes high-resolution spectral confocal opposite sensing technology for efficient wafer scanning.

(2) Equipped with a multi-degree-of-freedom electrostatic discharge coating vacuum chuck, supporting wafer sizes up to 12 inches.

(3) Employs Mapping follow technology, enabling programmable automatic measurements including multiple points, lines, and areas.

3. High-Precision 3D Topography Measurement Technology

(1) Uses optical white light interferometry, precision Z-axis scanning modules, and high-precision 3D reconstruction algorithms, achieving a Z-axis resolution as high as 0.1 nm.

(2) Vibration isolation design reduces ground vibration and airborne acoustic noise, ensuring high measurement repeatability.

(3) Machine vision technology detects image mark points, and virtual fixtures align samples, enabling automated continuous measurement of multiple topography points.

4. Large-Stroke High-Speed Gantry Structure Platform

(1) Large-stroke gantry structure (400x400x75 mm) with a movement speed of 500 mm/s.

(2) High-precision granite base and beam ensure overall structural stability and reliability.

(3) Key motion mechanisms use high-precision linear guides, AC servo direct-drive motors, and a grating system with 0.1 μm resolution, guaranteeing high precision and efficiency.

5. Simple Operation, Easy and Worry-Free

(1) Integrated joystick with XYZ directional displacement adjustment for quick stage translation and Z-axis focusing before measurement.

(2) Dual anti-collision design prevents damage to the objective lens and sample due to operational errors.

(3) Electric objective lens switching function for fast and simple observation.

Application Scenarios

1. Measurement of Unpatterned Wafer Thickness and Warpage

Through non-contact measurement, the 3D topography of both sides of the wafer is reconstructed. The powerful measurement and analysis software stably calculates wafer thickness, roughness, and total thickness variation (TTV), effectively protecting the integrity of wafers with films or patterns.

2. Roughness Measurement of Unpatterned Wafers

3D images of wafer surfaces after coarse and fine grinding in the thinning process. Surface roughness Sa values and the stability of repeated measurements are used to feedback processing quality. For thinned wafers measured in a high-noise production environment, the roughness of fine-ground wafers is concentrated around 5 nm. The repeatability calculated from 25 measurements is 0.046987 nm, indicating good measurement stability.

Please note: Due to market developments and product development needs, the content in this product documentation may be updated or modified at any time without prior notice. We appreciate your understanding.

If you have any questions or need more detailed information, please feel free to contact Chotest Instrument for consultation.