US Patent 11942549 Semiconductor device and method of manufacture

A semiconductor device and method of manufacture are provided. In embodiments a first liner is deposited to line a recess between a first semiconductor fin and a second semiconductor fin, the first liner comprising a first material. The first liner is annealed to transform the first material to a second material. A second liner is deposited to line the recess, the second liner comprising a third material. The second liner is annealed to transform the third material to a fourth material.