Method for fabricating oxide layer in semiconductor technology

• Main Authors: GARDNER, MARK, I, FULFORD, H. JIM, JR
• Format: Patent
• Language: English; French; German
• Published: 07.02.1996
• Edition: 6
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

In one embodiment a high-quality tunnel oxide suitable for programmable devices, such as EEPAL devices, is formed upon a surface region of a semiconductor body over a heavily-doped N+ layer, and a gate oxide is formed over a gate region, by first oxidizing the semiconductor body to form an initial oxide layer upon the surface region of the semiconductor body over the heavily-doped N+ layer and upon the surface of the gate region. Next, at least a portion of the initial oxide layer overlying the heavily-doped N+ layer is removed. The semiconductor body is then exposed to an environment suitable for oxidation, to thicken the remaining portions of the initial oxide, thereby forming the gate oxide, and to form the tunnel oxide over the heavily doped N+ layer. A concentration of nitrogen is introduced into both gate and tunnel oxides by introducing the semiconductor body to a source of nitrogen.