FinFET Having Isolation Structure and Method of Forming the Same

A method of making a transistor, comprising:

• forming a fin structure protruding from an upper surface of a substrate, the fin structure comprising a lower portion and an upper portion;
• forming a gate structure over the fin structure, the gate structure and the fin structure defining a drain region in the upper portion of the fin structure and a source region in the upper portion of the fin structure;
• patterning a recess in the drain region of the fin structure;
• and
• forming an isolation structure in the recess, wherein the isolation structure comprises a dielectric material, and wherein the fin structure surrounds the isolation structure in a top-down view.

A method comprising:

• forming a semiconductor fin extending upwards from a substrate;
• forming a gate stack over and along sidewalls of a first portion of the semiconductor fin;
• after forming the gate stack, etching a recess in a second portion of the semiconductor fin;
• and
• filling the recess with a dielectric material to define an isolation structure extending into the semiconductor fin, wherein top surfaces of the second portion of the semiconductor fin and the isolation structure are substantially level.