CCD图像传感器抗晕技术研究

Research of A CCD image sensor with a vertical anti-blooming structure

为了抑制CCD图像传感器在强光照射时出现光晕和弥散现象,建立了CCD纵向抗晕结构模型,运用半导体器件数值模拟软件MEDICI,对建立的纵向抗晕CCD器件结构进行数值计算。结果表明:CCD电极下的电荷容量随n沟道磷掺杂浓度的增加而迅速提高,但掺杂浓度的增加受期间体内击穿场强的限制,通过分析比较,取n沟道磷掺杂浓度为3×10^(16)cm^(-3)时抗晕效果较好,并得到了CCD纵向抗晕结构的一种优化结构。

A CCD image sensor is needed in order to eliminate blooming and smear. MEDICI is a powerful device simulation program that can be used to simulate the behavior of MOS and semiconductor devices. A simulation grid is created by MEDICI. Results show that the charge capacitances of CCD electrodes increase rapidly with the doping concentration under the channel, but the doping concentration increasing is constrained. Through analyses and comparison, the anti-blooming effect is good when n channel doping concentration Nch is 3 × 10^16cm^-3. An optimum structure is obtained.