Why Phase-Shifting Projection Moiré Outperforms Shadow Moiré for Thermal Warpage Measurement
The electronics industry is continuously pushing the limits of miniaturization and complexity, making the characterization of package warpage a significant challenge. At our company, we utilize advanced TDM technology to deliver highly accurate and reliable thermal warpage measurements. A key component of this technology is the Phase-Shifting Projection Moiré principle. While Shadow Moiré is a recognized method, a closer examination reveals that our approach is the superior choice.
The Foundational Principles
Both Shadow Moiré and Phase-Shifting Projection Moiré use optical techniques to measure the 3D shape of a surface. They do this by projecting a grating or light pattern onto an object and analyzing the resulting interference to determine its topography. However, the way each method handles this process leads to significant differences in performance and application.
Key Advantages of Phase-Shifting Projection Moiré
Based on an in-depth comparison of advanced package warpage measurement metrologies, our TDM technology, which is based on Phase-Shifting Projection Moiré, consistently demonstrates key advantages over Shadow Moiré.
Superior Sample Versatility: Unlike Shadow Moiré, which may require a deballing process and a coat of white paint for optimal results, our TDM technology eliminates the need for deballing and painting. This is a major advantage, as it saves significant sample preparation time and prevents potential damage or deformation that can occur during the deballing process. The ability to measure packages with BGAs (Ball Grid Arrays) intact is a key benefit, streamlining the testing workflow.
Higher-Quality Data: Shadow Moiré and Digital Fringe Projection (DFP) metrologies often employ smoothing algorithms to process raw data. The level of smoothing can affect the reported values, and it requires careful validation. In contrast, our technology, based on the DFP principle, can capture high-resolution data that, with proper software, can provide both substrate warpage and BGA coplanarity independently. Our Phase-Shifting Projection Moiré method enables the accurate detection of topographical deformations and coplanarity issues in devices under test, capturing measurements in real-time as devices undergo mechanical and thermal stress.
Flexible and Efficient Operation: Both Shadow Moiré and our TDM technology utilize a variable Field of View (FOV), which enables flexible imaging of various sample sizes or multiple units simultaneously. However, our systems are optimized for efficiency. The thermal chambers on our systems are equipped with convection and IR elements to achieve a broad temperature range from -65°C to 400°C. This dual-sided, dual-controlled IR heating system allows for continuous heating and cooling profiles, which are often more representative of a real SMT reflow process. It achieves smooth temperature ramps up to the peak. Our ramp rates, stability, and homogeneity exceed industry standards, making our technology a superior choice for measuring thermal warpage.
Meeting and Exceeding JEDEC Standards: Our TDM technology, based on Phase-Shifting Projection Moiré, excels at meeting industry standards. We provide high-resolution warpage graphs that are compliant with JEDEC and IPC standards. The JEDEC standard JESD-B108B outlines the coplanarity test for surface-mount semiconductor devices, which can be measured using either the seating plane or regression plane method. Our system's ability to measure packages with balls intact and utilize sophisticated software for analysis enables us to effortlessly meet these rigorous coplanarity test methods, giving you confidence in your results.
With TDM, you gain access to a comprehensive spectrum of analytical competencies, including 2D and 3D imaging, CTE and strain analysis, and vectorial plots. This wealth of information elevates your understanding and empowers your decision-making.
