FIELD

This disclosure relates to the field of semiconductor devices. More particularly, but not exclusively, this disclosure relates to bipolar junction transistors in semiconductor devices.

BACKGROUND

A semiconductor device may include a bipolar junction transistor. It is generally desirable for the bipolar junction transistor to have high gain, also referred to as hfe, and high Early voltage, also referred to as VA. Attaining both high hfeand high VAhas required additional process steps. Furthermore, known methods which may increase hfe(such as deeper emitter, higher base doping at the surface between emitter and base contacts, etc.) may affect the emitter and the base regions of the bipolar junction transistor.

SUMMARY

The present disclosure introduces a semiconductor device including a bipolar junction transistor. The bipolar junction transistor includes a collector with a current collection region, a constriction region laterally adjacent to the current collection region, and a contact region laterally adjacent to the constriction region, located opposite from the current collection region. The bipolar junction transistor includes a base with a current transmission region contacting the current collection region and a constricting well laterally adjacent to, and contacting, the current transmission region and contacting the constriction region.

