Abstract: A semiconductor structure for isolating a first circuit and a second circuit of various operating voltages includes a first isolation ring surrounding the first and second circuits on a semiconductor substrate. A buried layer continuously extending underneath the first and second circuits is formed on the semiconductor substrate, wherein the buried layer interfaces with the first isolation ring for isolating the first and second circuits from a backside bias of the semiconductor substrate. An ion enhanced isolation layer is interposed between the buried layer and well regions on which devices of the first and second circuits are formed, wherein the ion enhanced isolation layer is doped with impurities of a polarity type different from that of the buried layer.

Abstract: A semiconductor device includes multiple low voltage N-well (LVNW) areas biased at different potentials and isolated from a substrate by a common N+ buried layer (NBL) and at least one high voltage N-well (HVNW) area. The LVNW areas are coupled to the common, subjacent NBL through a common P+ buried layer (PBL). The method for forming the substrate usable in a semiconductor device includes forming the NBL in a designated low voltage area of a negatively biased P-type semiconductor substrate, forming the PBL in a section of the NBL area by implanting P-type impurity ions such as indium into the PBL, and growing a P-type epitaxial layer over the PBL using conditions that cause the P-type impurity ions to diffuse into the P-type epitaxial layer such that the PBL extends into the NBL. Low-voltage P-well areas are also formed in the P-type epitaxial layer and contact the PBL.

Abstract: A high-voltage transistor device with an interlayer dielectric (ILD) etch stop layer for use in a subsequent contact hole process is provided. The etch stop layer is a high-resistivity film having a resistivity greater than 10 ohm-cm, thus leakage is prevented and breakdown voltage is improved when driving a high voltage greater than 5V at the gate site. A method for fabricating the high-voltage device is compatible with current low-voltage device processes and middle-voltage device processes.

Abstract: A semiconductor structure for isolating a first circuit and a second circuit of various operating voltages includes a first isolation ring surrounding the first and second circuits on a semiconductor substrate. A buried layer continuously extending underneath the first and second circuits is formed on the semiconductor substrate, wherein the buried layer interfaces with the first isolation ring for isolating the first and second circuits from a backside bias of the semiconductor substrate. An ion enhanced isolation layer is interposed between the buried layer and well regions on which devices of the first and second circuits are formed, wherein the ion enhanced isolation layer is doped with impurities of a polarity type different from that of the buried layer.

Abstract: Method and apparatus for a semiconductor device including high voltage MOS transistors is described. A substrate is provided with a low voltage and a high voltage region separated one from the other. Isolation regions containing an insulator are formed including at least one formed within one of said wells within the high voltage region. The angle of the transition from the active areas to the isolation regions in the high voltage device region is greater than a predetermined angle, in some embodiments it is greater than 40 degrees from vertical. In some embodiments the isolation regions are formed using shallow trench isolation techniques. In alternative embodiments the isolation regions are formed using field oxide formed by local oxidation of silicon techniques.

Abstract: A semiconductor structure includes an isolation ring disposed on a semiconductor substrate, surrounding first and second circuit areas. A buried isolation layer is continuously extended through the first circuit area and the second circuit area, in the semiconductor substrate. The buried isolation layer interfaces with the isolation ring, thereby isolating the first and second circuit areas from a backside bias of the semiconductor substrate. An ion enhanced isolation layer separates the first well in the first circuit area and the second well in the second circuit areas from the isolation ring and the buried isolation layer, thereby preventing punch-through between the wells of the circuit areas and the buried isolation layer.

Abstract: A semiconductor device includes multiple low voltage N-well (LVNW) areas biased at different potentials and isolated from a substrate by a common N+ buried layer (NBL) and at least one high voltage N-well (HVNW) area. The LVNW areas are coupled to the common, subjacent NBL through a common P+ buried layer (PBL). The method for forming the substrate usable in a semiconductor device includes forming the NBL in a designated low voltage area of a negatively biased P-type semiconductor substrate, forming the PBL in a section of the NBL area by implanting P-type impurity ions such as indium into the PBL, and growing a P-type epitaxial layer over the PBL using conditions that cause the P-type impurity ions to diffuse into the P-type epitaxial layer such that the PBL extends into the NBL. Low-voltage P-well areas are also formed in the P-type epitaxial layer and contact the PBL.

Abstract: A semiconductor structure includes an isolation ring disposed on a semiconductor substrate, surrounding first and second circuit areas. A buried isolation layer is continuously extended through the first circuit area and the second circuit area, in the semiconductor substrate. The buried isolation layer interfaces with the isolation ring, thereby isolating the first and second circuit areas from a backside bias of the semiconductor substrate. An ion enhanced isolation layer separates the first well in the first circuit area and the second well in the second circuit areas from the isolation ring and the buried isolation layer, thereby preventing punch-through between the wells of the circuit areas and the buried isolation layer.

Abstract: A high-voltage transistor device with an interlayer dielectric (ILD) etch stop layer for use in a subsequent contact hole process is provided. The etch stop layer is a high-resistivity film having a resistivity greater than 10 ohm-cm, thus leakage is prevented and breakdown voltage is improved when driving a high voltage greater than 5V at the gate site. A method for fabricating the high-voltage device is compatible with current low-voltage device processes and middle-voltage device processes.

Abstract: Method and apparatus for a semiconductor device including high voltage MOS transistors is described. A substrate is provided with a low voltage and a high voltage region separated one from the other. Isolation regions containing an insulator are formed including at least one formed within one of said wells within the high voltage region. The angle of the transition from the active areas to the isolation regions in the high voltage device region is greater than a predetermined angle, in some embodiments it is greater than 40 degrees from vertical. In some embodiments the isolation regions are formed using shallow trench isolation techniques. In alternative embodiments the isolation regions are formed using field oxide formed by local oxidation of silicon techniques.

Abstract: A high voltage device comprising a substrate of a first type, a first and second well respectively of the first and a second type in the substrate, a gate formed on the substrate, a first and second doped region both of the second type, respectively formed in the first and second well and both sides of the gate, and a third doped region of the first type in the first well and adjacent to the first doped region.