Oxide deposition by using a double liner approach for reducing pattern density dependence in sophisticated semiconductor devices

A method of forming a semiconductor device, the method comprising:

• forming a first gate electrode structure above a first semiconductor region of said semiconductor device and a second gate electrode structure above a second semiconductor region of said semiconductor device;
• forming a silicon dioxide double liner above said semiconductor device, said silicon dioxide double liner comprising an undoped silicon dioxide layer and a hydrogen-containing silicon dioxide layer formed on said undoped silicon dioxide layer, said undoped silicon dioxide layer of said silicon dioxide double liner continuously covering at least an upper surface and sidewall surfaces of each of said first and second gate electrode structures and at least a portion of each of said first and second semiconductor regions and said hydrogen-containing silicon dioxide layer continuously covering an entirety of said undoped silicon dioxide layer, wherein forming said hydrogen-containing silicon dioxide layer comprises adjusting a process ambient used to form said undoped silicon dioxide layer by adding an additional hydrogen source to said process ambient and using said adjusted process ambient to form said hydrogen-containing silicon dioxide layer;
• and
• performing an etch process so as to form a spacer element from said silicon dioxide double liner at least on said sidewall surfaces of said first gate electrode structure, said undoped silicon dioxide layer contacting said sidewall surfaces.