Trench grate capable of improving trench grate MOS device performance and manufacture method thereof

• Main Authors: LIU XIANZHOU, KE LISI
• Format: Patent
• Language: Chinese; English
• Published: 29.09.2010
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

The invention provides a trench grate capable of improving trench grate MOS device performance and manufacture method thereof. In the prior art, the bottom end part of a grate dielectric layer is only silicon oxide, thereby grate drain capacitance is too large and in the manufacture process, over etching tends to appear, damage a silicon substrate and influence the performance of the device. The trench grate capable of improving the trench grate MOS device performance comprises the grate dielectric layer and a polycrystal grate layer, which are superposed in a grate groove. The grate dielectric layer is provided with a side wall part and a bottom end part, which are respectively arranged at the side wall and the bottom end of the grate groove. The side wall part is the silicon oxide. The bottom end part comprises a first silicon oxide layer, a chemical mechanical polishing stop layer and a second silicon oxide layer, which are superposed in turn. When the chemical mechanical polishing process of the silicon o