US Patent 7554171 Semiconductor constructions

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.