LDMOS (Lateral Double-diffused Metal Oxide Semiconductor Field Effect Transistor) device and manufacturing method

The invention discloses an LDMOS (Lateral Double-diffused Metal Oxide Semiconductor Field Effect Transistor) device. An N-type injection layer formed by high-dose N-type impurity injection is additionally arranged in a drift region consisting of an N-type epitaxial layer; a P-type auxiliary depletion layer formed by high-dose P-type impurity injection is formed below one side, close to a source end, of the N-type injection layer; and a P-type diffusion layer formed by diffusing impurities of a P+ buried layer in the N-type epitaxial layer is formed on one side, close to the source end, of the N-type injection layer. The invention further discloses a manufacturing method of the LDMOS device. According to the device and the manufacturing method, the breakover resistance of the device can be reduced; the breakover current of the device can be increased; the electric field intensity of the surface of the drift region can be reduced; the breakdown voltage of the device can be increased; a BCD (Bipolar-CMOS-DMOS) technology can be integrated; and no additional technology cost is increased.