| abstract |
A method including providing a substrate having a first region, a second region, and a third region defined thereupon. A first interfacial layer is formed over the first region, the second region, and the third region. The first interfacial layer is etched to remove a portion of the first interfacial layer from the first region and a portion of the first interfacial layer from the second region. Etching of the first interfacial layer defines a gate stack within the third region. After the etching of the first interfacial layer, a second interfacial layer is formed over at least a portion of the second region. The second interfacial layer is etched to define a gate stack within the second region. After the etching of the second interfacial layer, a third interfacial layer is formed on the substrate over at least a portion of the first region to define a gate stack within the first region. |