region that lies adjacent to n region 122 and eventually forward biases the junction between p region 114 and n region 122 when the increased potential forward biases the junction a npn transistor that utilizes n region 122 as the emitter p region 114 as the base and n material 112 as the collector turns on when turned on n emitter region 122 injects electrons into base material 114 most of the injected electrons diffuse through base material 114 and are swept from base material 114 into collector n material 112 by the electric field that extends across the reverse biased junction the electrons in collector n material 112 are then collected by n region 116 a small number of the electrons injected into base material 114 recombine with holes in base material 114 and are lost the holes lost to recombination with the injected electrons are replaced by holes injected into base material 114 by the broken down reverse biased junction and as described below by the collector current of a pnp transistor thereby providing the base current the electrons that are injected and swept into n material 112 also decrease the potential of n material 112 in the region that lies adjacent to p region 118 and eventually forward bias the junction between p region 118 and n material 112 when the decreased potential forward biases the junction between p region 118 and n material 112 a pnp transistor formed from p region 118 n material 112 and p region 114 turns on when turned on p emitter 118 injects holes into base 112 most of the injected holes diffuse through n material.