In order to ensure long-term use quality and reliability of PCB, we need to carry out SIR (Surface Insulation Resistance) test, through its test method to find out whether PCB will occur MIG(ion migration) and CAF(glass fiber anode leakage) phenomenon, Ion migration is performed in a humidified state (e.g. 85℃/85%R.H.) with a constant bias (e.g. 50V), the ionized metal moves between the opposite electrodes (cathode to anode growth), the relative electrode is reduced to the original metal and precipitated dendritic metal phenomenon, often resulting in short circuit, ion migration is very fragile, the current generated at the moment of power will make the ion migration itself dissolves and disappears, MIG and CAF commonly used norms: IPC-TM-650-2.6.14., IPC-SF-G18, IPC-9691A, IPC-650-2.6.25, MIL-F-14256D, ISO 9455-17, JIS Z 3284, JIS Z 3197... But its test time is often 1000h or 2000h, for the cyclical products is slow emergency, HAST is a test method and also the name of equipment, it can improve environmental stress (temperature, humidity, pressure), in the unsaturated humidity environment (humidity: 85%R.H.) Speed up test process and shorten test time, which can assess PCB pressing, insulation resistance, and the moisture absorption effect of related materials, shorten the test time of high temperature and humidity (85℃/ 85%R.H. /1000h→110℃/ 85%R.H. /264h), the main reference specifications of PCB HAST test are: JESD22-A110-B, JCA-ET-01, JCA-ET-08.
HAST Accelerated Life Mode:
1.Increase temperature (110℃, 120℃, 130℃)
2.Maintain high humidity (85%R.H.)
3.Taken the pressure (110 ℃ / / 0.12 MPa, 120 ℃, 85% / 85% / 85% 0.17 MPa, 130 ℃ / / 0.23 MPa)
4.Extra bias (DC)
HAST test conditions for PCB:
1.Jca-et-08:110, 120, 130 ℃/85%R.H. /5 ~ 100V
2. High TG epoxy multilayer board: 120℃/85%R.H./100V, 800 hours
3.Low inductance multilayer board: 110℃/85% R.H./50V/300h
4. Multi-layer PCB wiring, material: 120℃/85% R.H/100V/ 800h
5.Low expansion coefficient & low surface roughness halogen-free insulation material: 130℃/ 85% R.H/12V/240h
6.Optically active covering film: 130℃/ 85% R.H/6V/100h
7.Heat hardening plate for COF film: 120℃/ 85% R.H/100V/100h
Lab Companion HAST High Acceleration Stress Test System (JESD22-A118/JESD22-A110)
The HAST independently developed by Lab Companion with intellectual property rights, and the performance indicators can fully benchmark foreign brands. We have single-layer and double-layer models and two series of UHAST BHAST. Successful development of this system solves the problem of long-term dependence on imports and long delivery time also with high price. High Accelerated Stress Testing combines high temperature, high humidity, high pressure and time to measure the reliability of components with or without electrical bias. HAST testing accelerates the stress of more traditional testing in a controlled way. It is essentially a corrosion failure test. Corrosion-type failure acceleration can detect defects in packaging seals, materials and joints in a relatively short time.
