Understanding Smart Sensors - Nomads.usp

240 Understanding Smart SensorsWirebondsEpoxy globCopper padICCopper padPrinted circuit board substrate(a)SolderChipEpoxyencapsulationC4C4Ceramic substrateFigure 10.10 Epoxy protection for single die: (a) glob top and (b) flip-chip. (After: [13].)(b)silicon and the packaging for their intended applications. For example, severaltests have been developed for silicon pressure sensors based on the need todetect potential failures due to the environment in which the devices will operate.The tests have been used to qualify sensors with on-chip amplification. Keytests include but are not limited to the following [14]:• Operational life, such as pulse, pressure-temperature cycling with bias;• High humidity, high temperature with bias;• High temperature with bias;• High and low temperature storage life;• Temperature cycling;• Mechanical shock;• Variable frequency vibration;