| Chip Packaging Reliability Environmental Tests

MTT offers a complete range of chip packaging reliability environmental tests, including technical integration consulting, experimental design planning, hardware design and fabrication, environmental stress testing, and packaging quality testing. This one-stop service assists customers in achieving compliance with international reliability standards such as JEDEC, MIL-STD, and AEC-Q.

| What Are Chip Packaging Reliability Environmental Tests

The primary purpose of chip packaging reliability environmental stress tests is to evaluate the quality of semiconductor component packaging (Package Assembly). The key environmental factors affecting packaging quality include the temperature endurance level of the package structure, the resistance of the package structure to temperature and humidity, fatigue aging factors of the package structure, and finally, requirements related to storage and control.

The complexity of packaging reliability environmental stress tests has become increasingly diversified due to environmental changes, with traditional single tests gradually being replaced by more comprehensive and compound-effect approaches. For example, accelerated corrosion modes induced by acid rain and exhaust emissions derived from various types of air pollution at elevated temperatures can no longer be effectively verified using traditional concepts.

MTT offers a complete range of chip packaging reliability environmental tests, including technical integration consulting, experimental design planning, hardware design and fabrication, environmental stress testing, and packaging quality testing. This one-stop service assists customers in achieving compliance with international reliability standards such as JEDEC, MIL-STD, and AEC-Q.

| Environmental Stress Tests

1). Moisture Sensitivity Level (MSL) Classification

This classification applies to surface-mount devices (SMDs) and non-hermetic components, as well as other categories of parts that shall undergo the SMT reflow soldering process. The determination standard primarily relies on Scanning Acoustic Tomography (SAT, SAM, or CSAM) to identify the location and ratio of delamination, thereby establishing the corresponding moisture sensitivity level. Once the moisture sensitivity level is classified, it is then applied as a preconditioning step before conducting reliability tests. The purpose of preconditioning for reliability is to simulate the full cycle of a component from production, through transportation, to final customer use on the production line. The moisture absorption conditions during preconditioning are determined by the component’s moisture sensitivity level and also serve as a management reference for factory use. Many reliability environmental stress tests shall be preceded by preconditioning before they can commence.

2). Temperature Cycling Test

The temperature cycling test, also known as the “mother of reliability tests”, is one of the most critical assessments in reliability testing. By subjecting components to temperature cycling, mismatches in coefficients of thermal expansion are induced, which over time lead to fatigue aging of the components, ultimately resulting in failure. From the perspective of the component package, common issues observed include wire bond detachment, structural delamination, metal fracture, and solder joint fatigue cracking, making it one of the closest simulations to real-world operating conditions.

3). Temperature Humidity Bias (THB) Test

This test exposes components to high-temperature and high-humidity environments while applying electrical bias, creating accelerated chemical reactions that cause corrosion phenomena. In addition to static environmental tests, bias testing is frequently used as it provides clearer insight into the risk of ionic migration within the metallic materials of the package, while also allowing simultaneous evaluation of the product’s corrosion resistance. Due to the long duration of the conventional test, a Highly Accelerated Stress Test (HAST) can be used as a substitute. The key difference lies in the humidification process: at higher temperatures, greater atmospheric pressure is generated, which accelerates the rate of corrosion. According to the JEDEC definition, a 96-hour HAST can be used to replace a 1000-hour high-temperature/high-humidity test (85 °C / 85% RH).

4). High / Low Temperature Storage Test

The purpose of this test is to verify the thermal aging status of packaging materials by accelerating material degradation under prolonged high-temperature or low-temperature conditions. For the low-temperature test, mechanical deformation is induced by expansion and contraction at extremely low temperatures. This results in embrittlement of the component structure and the formation of cracks. Since the high/low temperature storage test targets the aging of packaging materials rather than the packaging structure itself, the test can be conducted without preconditioning procedures.

5). Thermal Resistance Test

Since most electronic products shall undergo processes involving heat, such as assembly, disassembly, and repair, they shall withstand various thermal resistance simulations to ensure that these procedures do not cause thermal shock damage. Common methods include reflow soldering, soldering iron, hot air gun, and solder dipping.

| Package Quality Test

1). Solderability Test

The purpose of the solderability test is to ensure the plating quality of component leads or to detect whether solder balls are affected by contamination issues. The standard experimental method is the solder pot process, which shall achieve a coverage rate of no less than 95%. For BGA solder ball solderability tests, although there are currently no regulatory standards, the industry generally adopts SMT process simulation, which more closely reflects actual application conditions.

2). Wetting Balance Test

The purpose of the wetting balance test is to resolve disputes regarding solderability. By using a highly sensitive wetting balance, the contact reaction speed between component leads and solder can be determined, allowing for the prediction of potential risks. This method compensates for blind spots in solderability testing and also provides an effective means for verifying expired materials.

3). Pull / Shear Test

The pull/shear test is primarily aimed at evaluating the quality of the wire bonding process in packaging. Through this test, pull and shear force values are collected for SPC (Statistical Process Control) calculation to determine variation and drive continuous optimization. In addition, for BGA solder balls, shear force testing can be conducted, referencing the AEC-defined solder ball shear force values to determine compliance, thereby ensuring that solder joint bonding strength meets the required standards.

4). Pb-Free Test

The Pb-free process test is a broadly defined category. Electronic products have adopted lead-free processes for approximately fifteen years, and the technology has already become relatively mature. In recent years, as the automotive market began adopting Pb-free processes, the need for tin whisker testing has re-emerged. Consequently, Pb-free testing has become a standard requirement in the field of automotive electronic products.

| MTT Advantages

1. Professional Team: A team of highly experienced testing engineers and technical experts.

2. Advanced Equipment: Equipped with internationally leading testing instruments to ensure accuracy and reliability of results.

3. Efficient Service: Rapidly respond to customer needs and provide one-stop, high-efficiency inspection services.

4. Authoritative Certification: The laboratory is certified by ISO/IEC 17025, ensuring that test reports have international credibility.