Reliability tests are being done to determine the workability of semiconductor devices after board mounting in real life applications and in operating conditions that can either

• Be exposed to by normal users
• Be so extreme that passing them makes "normal" everdat use a cakewalk.

Different reliability requirements are being imposed by different sectors and industries such as the Automotive industryor the Aerospace and military sectors.

Regardless, the testing methods are pretty standard and only the conditions that the packages need to withstand are the changing.

Common Reliability tests:

• T/C Test(Temperature Cycling Test)     
• T/S Test(Thermal Shock Test) 
• HTST(High Temperature Storage Test) In Air or N2 chamber
• T&H Test(Temperature & Humidity Test) 85/85, 1000hrs
• PCT (Pressure Cooker Test) (168hr, 121C, Saturated Vapor 100%RH, QFP products)
• HAST(Highly Accelerated Stress Test) (168hr, 130C, unsaturated vapor, 80%RH, BGA products)