iST Introduces the Sulfur Corrosion Verification on Passive Components

iST Introduces the Sulfur Corrosion Verification on Passive Components

The proliferation of Artificial Intelligence (AI), big data, 5G, electric vehicles, Internet of Things (IoT), Edge Computing, High Performance Computing (HPC) and Electric Vehicle (EV) in recent years has necessitated the increased use of electronic passive components. Therefore, the hardware reliability of electronics has received more attention in the industry. With prevalent environmental pollution, air quality will also directly or indirectly influence the life of electronics in indoor and outdoor applications. To assist customers in ensuring the quality of passive components, iST (Integrated Service Technology) announces today (August 17, 2021) that it is introducing the verification of sulfur corrosion occurrence on passive components to help customers accelerate time-to-market, and reduce returns.

iST said, the hardware reliability of electronics can be easily affected by corrosive gases, moisture, salts, contaminants and particulate matter, especially in environments with high sulfur-bearing gaseous contamination, which can potentially cause the electrical open failure on passive components. For example, SMT resistors and ferrite beads, silver (Ag) is often used as the main material for inner layer electrodes. However, is easily corroded by sulfur (S) and gradually transforms into silver sulfide (Ag₂S). It will induce an open circuit as no current flows between both terminals of a SMT resistor since Ag2S is non-conductive which causes the resistance value to increase.

Figure: Sulfur corrosion occurrence on SMT resistors

(Source: Dr. Gert Vogel, Siemens AG, Amberg, Siemens, 2017 &iST Lab)

In the light of the above, the Electronic Components Industry Association (ECIA) has published a standard: ANSI/EIA-977 standard which defines options for testing passive electronic components for susceptibility to the effects of environmental sulfur in Feb, 2017. Such susceptibility results in the corrosion of silver in the presence of sulfur compounds in a liquid or gaseous state, potentially leading to component failure. ANSI/EIA-977 test is a basic necessity for the anti-sulfur corrosion capacity discrimination of electric anti-sulfur passive components in industry.

In order to improve the robustness against sulfur corrosion, many vendors provide Anti-Sulfur Resistors (ASR) which adopted gold-based and silver-palladium-based inner electrode designs (noble metal) as well as other solutions, including passivation cover, nanowire silver electrode and reverse structure designs, iST further pointed.

iST said, under the increasing threat of global air pollution, the next generation electronics required not only high performance but also robustness against harsher environments. iST provides the various sulfur corrosion resistance tests, and also assess the corrosion simulation with long-term exposure at ISA 71.04-2013 G2, G3 severity level or field environment. Besides, we can adopt the customized design of experiment to assess the anti-sulfur corrosion life time through the accelerated test to help customers accelerate time-to-market, and reduce returns.