Transistor structure with reduced parasitic side wall characteristics

摘要

A MOS transistor structure for matched operation in weak-inversion or sub-threshold range (e.g. input-pair of operational amplifier, comparator, and/or current-mirror) is disclosed. The transistor structure may include a well region of any impurity type in a substrate (SOI is included). The well-region can even be represented by the substrate itself. At least one transistor is located in the well region, whereby the active channel-region of the transistor is independent from lateral isolation interfaces between GOX (gate oxide) and FOX (field oxide; including STI-shallow trench isolation).

主权项

1. A transistor structure, comprising:
a substrate; a well region of a first impurity type in the substrate; at least one transistor formed at least partially on the well region, a portion of the well region comprising a transistor channel; a structure of the first impurity type in the substrate enclosing the well region; and an isolation layer on a portion of the substrate surrounding the structure; wherein a concentration of the first impurity type in the structure enclosing the well region is higher than a concentration of the first impurity type in the well region.