Trench isolation structure having isolating trench elements

A semiconductor device comprising a semiconductor substrate, the semiconductor substrate comprising in one main surface of the semiconductor substrate:

• an element isolating trench;
• and
• a semiconductor element that is formed in an element formation region,
• wherein the element isolating trench has
• (i) a first side that connects a first point and a second point,
• (ii) a second side that connects the first point and a third point, and that forms an angle “90°−θ” (0°<θ<90°) with the first side,
• (iii) a third side that faces the first side across the element isolating trench, and that runs parallel to the first side,
• (iv) a fourth side that faces the third side across the element formation region, and that runs parallel to the third side, and
• (v) a fifth side that is disposed on a first line that extends at a right angle with respect to the first side, and that connects a fourth point that is an end point of the third side and a fifth point that is an end point of the fourth side.