Environmental Stress Testing
Environmental Stress Test is aimed at electronic components and products underreliability and durability under extreme usage conditionsThe systematic verification conducted aims to confirm whether the assembly quality of the components is sufficient to support actual application requirements. The main evaluation focuses on three key aspects:The temperature resistance, moisture absorption and moisture resistance of the package, as well as the stability of preservation and process control.。
From the completion of component manufacturing to entering the SMT or DIP assembly process, the first challenge faced is the thermal shock caused by high-temperature reflow soldering; subsequently, during the actual use phase of the product, prolonged temperature, humidity, and environmental stress will further affect the component's lifespan and failure rate. Therefore, environmental stress testing is an essential key verification process before the product enters mass production and the market.
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Moisture Sensitivity Level / MSL
Mainly aimed at verifying surface mount devices (SMD) or components that have undergone the SMT reflow process. The judgment method primarily uses ultrasonic scanning (SAT or SAM) to determine the delamination (Delamination) location and delamination ratio, and thereby establish the moisture sensitivity level.
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Precondition Test
The testing method is similar to that of humidity sensitivity levels, but the purpose is different. The purpose of preconditioning is to simulate the cycle process of parts from production, transportation, to the customer's online usage. The moisture absorption conditions for preconditioning are based on the humidity sensitivity level of the parts, but due to the similar processes, many component manufacturers in the industry combine these two operations based on experience.
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Temperature Cycling Test
Temperature cycling testing is a very important part of reliability testing. By alternating the parts between cold and hot for several cycles, the impact of fatigue aging on the product is examined through the difference in the coefficient of expansion. This experiment is the most commonly used reliability testing standard and is similar to the actual usage conditions of the product during power on and off. -
High Temperature Storage Test
The purpose of this test is to verify the thermal aging state of the packaging material, accelerating the aging of the packaging material under continuous high temperature conditions.
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Low Temperature Storage Test
The purpose of this test is to verify the low-temperature resistance of packaging materials. At extremely low temperatures, mechanical deformation caused by expansion and contraction is used to examine the cracks induced by embrittlement of the component structure. -
Temperature Humidity Storage Test
Through high temperature and humidity environments, the corrosion phenomenon of components caused by accelerated chemical reactions is often tested using bias testing of the metallic materials of the package, in addition to static environment tests, to simultaneously test the product's corrosion resistance.
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Highly Accelerated Stress Test
Similar to the principle of temperature and humidity storage testing, the difference lies in the fact that during the humidification process, a higher temperature creates an environment with pressure greater than atmospheric pressure, which accelerates the corrosion rate, leading to internal corrosion of poorly packaged products. -
High Temperature Steam Pressure Test (Pressure Cook Test)
This experiment provides an environment of two atmospheric pressures, usually used for process quality verification, to test the moisture resistance of semiconductor packaging. If unreliable testing methods are used, some materials, such as BGA substrates, may suffer excessive damage.
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Temperature shock test (Thermal shock Test / Liquid to Liquid)
Similar to the principle of temperature cycling tests, the difference is the accelerated temperature change rate, which measures the product's resistance when exposed to extreme high and low temperatures. It can detect defects such as packaging seals, grain bonding, wire bonding, and substrate cracks. -
Dual Chamber Thermal Shock Test (Thermal Shock Test / Air to Air)
Unlike the traditional TCT test temperature change rate, the dual-slot temperature shock testing machine is suitable for larger samples and can transfer the test item from one temperature to another in a very short time, making it more representative for verification in specific environments such as automotive products.
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Salt Spray Test
The salt spray test can simulate the metal corrosion conditions of parts used in harsher environments. This test mainly focuses on the quality of metal surface treatment, especially when products are used in island environments or areas with high salinity. It is well-known that products may experience poor contact due to accelerated corrosion, and the salt spray test can quickly verify the process or manufacturing quality.
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Gas Corrosion
Due to the increasingly serious air pollution on Earth, being in such an industrial environment, whether from factories or exhaust emissions from vehicles, can cause harm to various electronic products. The purpose of gas corrosion testing is mainly to verify the corrosion resistance quality of the electroplating or coating on the surface of products or components, to ensure the lifespan of the products. Unlike salt spray testing, gas corrosion testing has a broader scope and is closer to actual application environments.
MA-tek gathers industry veterans with many years of experience in semiconductor component reliability testing. To provide customers with a more convenient service platform, it has also established a dedicated window for integrated technical services (Total Solution), offering experimental design and overall planning, among other services. To ensure the stability of experimental quality, the company uses internationally renowned brand equipment, providing customers with the most stable test results and the best testing environment. According to the technical specifications of the product and customer requirements, MA-tek can perform reliability testing according to various standards such as MIL-STD, JEDEC, IEC, JESD, AEC, EIA, etc.
When designing products, various materials and assembly methods are used, and each component reacts differently under high and low temperatures, humidity, or prolonged stress. Additionally, the diverse usage environments of consumers lead to varying reliability considerations depending on the application scenario. Common sources of environmental stress include:
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Temperature factors (high temperature, low temperature, rapid heating, rapid cooling, temperature cycling)
In a dynamic temperature environment, the speed of chemical reactions increases, and materials may undergo structural deformation due to thermal expansion and contraction, which can effectively expose potential issues with solder joints, packaging, or structures. -
Humidity factor (high humidity, temperature and humidity cycling)
High humidity can lead to corrosion, leakage, or moisture absorption and swelling; if high temperatures are encountered simultaneously, materials are even more likely to undergo cracking. -
special environments (low temperature and low humidity, high altitude, corrosive gases, sunlight, sand and dust)
For example: Low temperature and low humidity environments can easily lead to static electricity accumulation; acid rain can accelerate metal corrosion; outdoor equipment must face sunlight exposure and rain impact, and its waterproof and dustproof capabilities are further tested.
Therefore, Environmental stress testing can verify the reliability and lifespan of products in extreme environments in advance, preventing failures after market launch.to make the product more stable and durable in real-world situations.
Different products require different test combinations.
Compared to the standardized testing procedures for electronic components,Complete machine products must choose suitable test factors based on the actual usage environment. The higher the complexity of the product, the more detailed the reliability considerations.e.g.,
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Outdoor equipment:Need to conduct sunlight, rain, dust, water, and corrosion tests.
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Automotive electronics:More sensitive to temperature cycling, humidity, and corrosion.
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Aerospace / High-altitude Applications:Must pass high-altitude decompression test.
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Industrial Equipment:It is necessary to emphasize the combined testing of temperature and humidity and long-term reliability.
