SCR-based ESD protector in SiGe process

An SCR-based ESD protector in an SiGe process comprises a substrate, an n well region, a p well region, an isolation groove, an n well contact n+ region, a SiGe_p+ region, an n+ region and a p well contact p+ region which are sequentially arranged from bottom to top. Obvious protrusions exist on an energy band at the interface of an SiGe_p+ layer and the n well region, so that injection of carriers is hindered, the gain of a parasitic PNP tube is reduced, and a positive feedback mechanism in an SCR is weakened. According to the SCR-based novel ESD protection device under the SiGe process, the maintaining voltage can be remarkably improved under the condition that the key parameters, such as the structure doping concentration, the size, etc., of a conventional SCR-based ESD protection device are not changed, and the SCR-based novel ESD protection device can be better suitable for a low-voltage narrow window in the field of integrated circuit ESD protection. SiGe工艺中基于SCR的ESD防护器，包括自下而上依次设置衬底，n阱区，p阱区，隔离槽，n阱接触n+区，