When the characteristic size reach micron, submicron degree, overcoming the "limit" binding in order to increase the integration of device.
当特征尺寸进入到微米、亚微米量级时，需要克服“极限”束缚，增加器件的集成度。
2
The pretreatment conditions of sample, background absorption interference, the detection limit and characteristic concentration were investigated.
对样品处理条件、背景吸收干扰、出限及特征浓度进行了考察。
3
The paper introduced setting principle, calculation and testing method for the low exciting limit unit using the static out of step characteristic circle.