Abstract: An embodiment of a NOR Flash device manufacturing method is disclosed, which includes: providing a substrate having a first polycrystalline silicon layer disposed thereon; forming a first hard mask layer on the first polycrystalline silicon layer; etching the first hard mask layer to form a first opening, and cleaning a gas pipeline connected to an etching cavity before etching the first hard mask layer; forming a second hard mask layer on the first hard mask layer, and the second hard mask layer covers the bottom and side wall of the first opening; etching the second hard mask layer to form a second opening, the width of the second opening is smaller than the width of the first opening; etching the first polycrystalline silicon, forming a floating gate. The NOR Flash device manufacturing method of the present invention improves the yield of the NOR Flash device.

Abstract: A read-only memory includes a plurality of storage units arranged in an array. The read-only memory includes two kinds of storage units with different structures, the two kinds of storage units with different structures are a first MOS transistor and a second MOS transistor. A source and a drain of the first MOS transistor have the same type, a source and a drain of the second MOS transistor have inverse type. These two kinds of MOS transistors can be used to store binary 0 and 1 respectively. In the manufacturing method of the read-only memory, the same type of drain and source can be manufactured simultaneously, no extra mask plate is needed, so the extra mask plate of a conventional read-only memory can be saved.

Abstract: A method for manufacturing a bipolar transistor includes forming a first epitaxial layer on a semiconductor substrate, forming a second epitaxial layer on the first epitaxial layer, forming an oxide layer on the second epitaxial layer, etching the oxide layer to form an opening in which the second epitaxial layer is exposed, and forming a third epitaxial layer in the opening. The first and third epitaxial layers have a first-type conductivity, and the second epitaxial layer has a second-type conductivity.

Abstract: A method is disclosed for manufacturing a semiconductor device. The method includes providing a substrate and forming a well region in the substrate by an ion implantation. The method also includes forming, by rapid thermal oxidation and on the substrate having the well region, an oxide layer for repairing the substrate damaged by the ion implantation. Further, the method includes removing the oxide layer and forming a gate oxide layer on the repaired substrate having the well region.

Abstract: A lithium battery protection circuit coupled to a lithium battery is provided. The lithium battery protection circuit includes an over-charge protection circuit and a logic circuit coupled to over-charge protection circuit. The logic circuit has a first logic output and a second logic output. The lithium battery protection circuit also includes a level shift circuit coupled to the logic circuit through the first logic output and the second logic output, and the level shift circuit is configured to convert the first logic output and the second logic output to high voltage levels in an over-charge protection state. Further, the lithium battery protection circuit includes a substrate switching circuit coupled to the level shift circuit and a power transistor coupled between a negative end of the lithium battery and an external circuit negative electrode.

Abstract: A method for fabricating VDMOS devices includes providing a semiconductor substrate; forming a first N-type epitaxial layer on the semiconductor substrate; forming a hard mask layer with an opening on the first N-type epitaxial layer; etching the first N-type epitaxial layer along the opening until the semiconductor substrate is exposed, to form P-type barrier figures; forming a P-type barrier layer in the P-type barrier figures, the P-type barrier layer having a same thickness as that of the first N-type epitaxial layer; removing the hard mask layer; forming a second N-type epitaxial layer on the first N-type epitaxial layer and the P-type barrier layer; forming a gate on the second N-type epitaxial layer; forming a source in the second N-type epitaxial layer on both side of the gate; and forming a drain on the back of the semiconductor substrate relative to the gate and the source.

Abstract: A method for manufacturing a bipolar transistor includes forming a first epitaxial layer on a semiconductor substrate, forming a second epitaxial layer on the first epitaxial layer, forming an oxide layer on the second epitaxial layer, etching the oxide layer to form an opening in which the second epitaxial layer is exposed, and forming a third epitaxial layer in the opening. The first and third epitaxial layers have a first-type conductivity, and the second epitaxial layer has a second-type conductivity.

Abstract: A method for fabricating trench DMOS transistor includes: forming an oxide layer and a barrier layer with photolithography layout sequentially on a semiconductor substrate; etching the oxide layer and the semiconductor substrate with the barrier layer as a mask to form a trench; forming a gate oxide layer on the inner wall of the trench; forming a polysilicon layer on the barrier layer, filling up the trench; etching back the polysilicon layer with the barrier layer mask to remove the polysilicon layer on the barrier layer to form a trench gate; removing the barrier layer and the oxide layer; implanting ions into the semiconductor substrate on both sides of the trench gate to form a diffusion layer; coating a photoresist layer on the diffusion layer and defining a source/drain layout thereon; implanting ions into the diffusion layer based on the source/drain layout with the photoresist layer mask to form the source/drain; forming sidewalls on both the sides of the trench gate after removing the photoresist la