Wimpy device by selective laser annealing

Abstract

A method for co-integrating wimpy and nominal devices includes growing source / drain regions on semiconductor material adjacent to a gate structure to form device structures with a non-electrically active material. Selected device structures are masked with a block mask. Unmasked device structures are selectively annealed to increase electrical activity of the non-electrically active material to adjust a threshold voltage between the selected device structures and the unmasked device structures.

Description

BACKGROUNDTechnical Field[0001]The present invention generally relates to semiconductor processing, and more particularly to methods and devices having a combination of wimpy and nominal devices integrated together by employing a selective anneal, e.g., laser annealing.Description of the Related Art[0002]Devices in non-critical circuit paths are preferred to have larger threshold voltages (Vt) than nominal devices. This assists in maintaining low leakage rates while not compromising circuit performance. These devices with larger Vt are called ‘wimpy’ devices. Conventionally, wimpy devices are made with larger gate lengths (Lg) and have higher channel doping than the nominal devices. These features employ special device and mask designs and require additional steps of lithography and implantation.[0003]As devices scale down, making wimpy devices with larger Lg and a same contacted gate (poly) pitch (CPP) as for the nominal devices is impractical because there is very little room for ...

AI Technical Summary

Benefits of technology

The present invention provides methods for integrating wimpy and nominal devices by co-integrating source / drain regions on semiconductor material adjacent to a gate structure with non-electrically active material. Selected device structures are masked with a block mask and unmasked device structures are selectively annealed to increase electrical activity of the non-electrically active material to adjust a threshold voltage between the selected device structures and the unmasked device structures. The invention also provides a device having co-integrated wimpy and nominal transistors, which have different threshold voltages. The technical effects of the invention include improved performance and reliability of complementary MOSFETs and the ability to adjust threshold voltage for better circuit performance.

Problems solved by technology

As devices scale down, making wimpy devices with larger Lg and a same contacted gate (poly) pitch (CPP) as for the nominal devices is impractical because there is very little room for contacts, among other things.

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