Abstract: A method of forming an integrated circuit includes forming a first trench that extends into the semiconductor substrate. A silicon nitride layer is deposited over the semiconductor substrate. The silicon nitride layer extends into the first trench. A second trench is formed that extends through the silicon nitride layer into the semiconductor substrate. The second trench is spaced apart from the first trench. An oxide layer is formed that fills the second trench. The silicon nitride layer outside the first trench is removed.

Abstract: The invention includes a method of forming a planarized surface over a semiconductor substrate. A substrate is provided which includes a memory array region and a peripheral region proximate the memory array region. The memory array region has a higher average elevational height than the peripheral region. Polysilazane is formed over the memory array region and over the peripheral region. The polysilazane is densified. A material is formed over the polysilazane. The material is planarized while using the densified polysilazane as a stop. The planarization forms a planarized surface which extends over the memory array and peripheral regions. The planarized surface comprises both the densified polysilazane and the material.

Abstract: The invention includes a method of forming a planarized surface over a semiconductor substrate. A substrate is provided which includes a memory array region and a peripheral region proximate the memory array region. The memory array region has a higher average elevational height than the peripheral region. Polysilazane is formed over the memory array region and over the peripheral region. The polysilazane is densified. A material is formed over the polysilazane. The material is planarized while using the densified polysilazane as a stop. The planarization forms a planarized surface which extends over the memory array and peripheral regions. The planarized surface comprises both the densified polysilazane and the material.