Industry observation | introduction to electronic components 'shelf life', after the expiration of the quality and how to ensure reliability?
Most electronic products in certain environmental condition for quality after a period of time often changes, components is no exception.
When stored more than the prescribed time limit, the quality and reliability will not guarantee, so must provide a storage period, can also be understood as 'shelf life' of food safety.
Components of the storage period is finished from production and inspection to the installed before storage time under certain environmental conditions, and the components of effective storage period refers to the quality and reliability of the components in the storage period before the machine can meet the deadline set by our equipment, basic validity is not considering the effective storage time of component quality.
Factors that affect components storage period 】
Decision component the length of the valid storage period is closely related to the following three factors: (
The quality of the components (
, is to ensure that the components in the effective storage period the basis of quality and reliability will not significantly degraded condition;
Components of storage environment conditions;
Qualified criterion of the components after storage.
10℃~ + 40℃,相对湿度≤80%;
遍及为20% ~ 70%;
Air pressure is 70 kpa to 106 kpa.
表1贮存环境条件分类i, ii, iii类环境条件各不相同。
According to the storage environment conditions of special components, such as components that are sensitive to electrostatic discharge (
The MOS devices, microwave devices, etc. )
Sensitive to magnetic field five components of magnetic mask, but is should be stored in a container with magnetic masking effect is;
The sealing sheet components should be stored in inert gas seal container, or stored in taking effective anti-oxidation;
Micromotor, such as mechanical and electrical components of the oil seal and the unit packing should be intact.
Components of the effective storage period.
MIL - after release
The European space agency (
The ESA PSS -
Which can be concluded that esa for the components of the storage period for 5 years.
Above standard specification, with the development of the semiconductor device manufacturing technology and the increase of the cognition of objective things, people effective storage period and thus prolong the microelectronic device.
3 years or 5 years)
, but did not say what is in the storage environment of effective storage period.
Moreover, different kinds of components in different aspects such as structure, material, process, so the effective storage period should also be different.
But Europe and the United States will all components of the effective storage period shall be classified as 3 years or 5 years, this way may lack the scientific basis.
称呼针对欧美元器件有奉行效贮期这些问题,标准qj2222a及gjb / z123则明确了不同前器件上各自有奉行效贮期,该时不到前考虑回收器件质量等级与前器件有奉行效贮期关系,典型器件如表2所示。