Structures and methods for fabricating semiconductor devices using fin structures

A method comprising:

• forming a shallow trench isolation (STI) structure on a substrate;
• removing part of the STI structure to form a first fin structure and a second fin structure extending above a support structure on the substrate;
• wherein:
• a first part of the STI structure is located between the first fin structure and the second fin structure and has a first top surface higher than an interface between the first fin structure and the support structure;
• and
• a second part of the STI structure is located adjacent to the first fin structure and has a second top surface lower than the interface between the first fin structure and the support structure;
• performing an etching process to remove part of the first fin structure and the second fin structure, part of the support structure adjacent to the second part of the STI structure being removed during the etching process;
• and
• forming a fin-end source/drain region adjacent to the second part of the STI structure and an in-fin source/drain region adjacent to the first part of the STI structure, a first volume associated with the fin-end source/drain region being larger than a second volume associated with the in-fin source/drain region.