Abstract: The present disclosure provides a wafer that can be used in coating films. The wafer includes a front surface, a back surface opposite to the front surface, and a plurality of trenches. The back surface further includes a central region and a surrounding region. The trenches are disposed on the back surface. The spacing between any two adjacent trenches in surrounding region is less than the spacing between any two adjacent trenches in the central region.

Abstract: The present disclosure provides a wafer that can be used in coating films. The wafer includes a front surface, a back surface opposite to the front surface, and a plurality of trenches. The back surface further includes a central region and a surrounding region. The trenches are disposed on the back surface. The spacing between any two adjacent trenches in surrounding region is less than the spacing between any two adjacent trenches in the central region.

Abstract: A manufacturing method of STI in DRAM includes the following steps. Step 1 is providing a substrate and step 2 is forming at least one trench in the substrate. Step 3 is doping at least one of side portions and bottom portions of the trench with a dopant. Step 4 is forming an oxidation inside the trench and step 5 is providing a planarization step to remove the oxidation. The stress of the corners of STI is reduced so as to modify the defect of the substrate and improve the DRAM variability in retention time.

Abstract: Methods of forming dual gate oxides are provided. A first gate oxide layer and oxynitride layer is formed over a substrate. A portion of the first gate oxide and oxynitride layers is removed over a second area of the substrate, and a second gate oxide is formed thereon. The first gate oxide layer is simultaneously reoxidized. The reoxidized first gate oxide layer incorporates oxynitride and is thinner than a second gate oxide layer. Methods of forming the semiconductor devices and memory cells are also provided. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that is will not be used to interpret or limit the scope or meaning of the claims.

Abstract: Methods of forming dual gate oxides are provided. A first gate oxide layer and oxynitride layer is formed over a substrate. A portion of the first gate oxide and oxynitride layers is removed over a second area of the substrate, and a second gate oxide is formed thereon. The first gate oxide layer is simultaneously reoxidized. The reoxidized first gate oxide layer incorporates oxynitride and is thinner than a second gate oxide layer. Methods of forming the semiconductor devices and memory cells are also provided. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that is will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).