抄録
Fatigue behavior of single crystal silicon wafer was examined under bending load in three different environments, lab air, liquid water and 80% relative humidity (RH), to see the effect of relative humidity and liquid water on the fatigue lifetime. Static strength was obtained in advance to fatigue test, where the strength in 80% RH decreased significantly in comparison to those in other two cases. In fatigue test also, the lifetime in 80% RH was slightly shorter when compared under the same stress level normalized to the static strength in each environment. In contrast, the strength and lifetime in liquid water had almost no difference from those in lab-air. These results suggested that highly humid environment have much greater impact on both the strength and fatigue lifetime of silicon than that of liquid water.
