Abstract: A method for fabricating oxide layers with different thicknesses on a substrate is described. A field oxide layer is formed on the substrate to define a first active region and a second active region therebetween. A first oxide layer is formed over the first active region. A thin oxynitride layer is formed on the first oxide layer.

Abstract: A method for fabricating oxide layers with different thicknesses on a substrate is described. A field oxide layer is formed on the substrate to define a first active region and a second active region therebetween. A first oxide layer is formed over the first active region. A thin oxynitride layer is formed on the first oxide layer.

Abstract: A method for preventing bonding pads from peeling caused by plug process comprises the following steps. First, a substrate is prepared, and then a first conductor is formed on the substrate. Next, a dielectric layer is formed on the first conductor. After that, a big contact window and a plurality of small contact windows are formed on the dielectric layer, wherein the plurality of small contact windows are located around the big window, and the sizes of the big contact window and small contact windows are over 3 .mu.m. Subsequently, a metal plug layer is formed on the dielectric layer, big contact window and small contact windows. Thereafter, the metal plug layer is etched back to form metal spacers on the sidewalls of the big contact window and small contact windows. Finally, a second conductor is formed on the dielectric layer, big contact window, small contact windows and metal spacers.