Renesas Electronics Corporation

Nec Electronics Corporation

Yoshimitsu Murase

Kenya Kobayashi

Atsushi Kaneko

Hideo Yamamoto

A semiconductor device includes a semiconductor layer of a second conductive type, a first diffused region of a first conductive type formed in the semiconductor layer, a second diffused region of the second conductive type selectively formed in the first diffused region, a trench formed in the semiconductor layer, a gate electrode housed in the trench with a gate insulator intervening, a top surface of the gate electrode being lower than a top surface of the second diffused region, a first oxide film housed in the trench and formed over the gate electrode, a second oxide film housed in the trench and formed over the first oxide film, a third oxide film housed in the trench and formed over the second oxide film, and a source electrode formed over the third oxide film and electrically connecting to the first and second diffused regions.

Semiconductor device and method for manufacturing the same

A semiconductor device includes a semiconductor layer, a first diffused region formed in the semiconductor layer, a second diffused region formed in the first diffused region, a trench formed in the semiconductor layer, a gate electrode disposed in the trench, a top surface of the gate electrode being lower than a top surface of the semiconductor layer and sagging downwards in a center thereof, a non-doped silicate glass film disposed in the trench and formed over the gate electrode, a top surface of the silicate glass film sagging downwards in a center thereof, an oxide film disposed in the trench and formed over the non-doped silicate glass film, a top surface of the oxide film sagging downwards in a center, and a source electrode formed over the semiconductor layer so that the source electrode contacts the first and second diffusion regions, and the oxide film at the top surface thereof.

A semiconductor device, includes a semiconductor layer of a second conductive type, a first diffused region of a first conductive type formed in the semiconductor layer, a second diffused region of the second conductive type selectively formed in the first diffused region, a trench formed in the semiconductor layer, a polysilicon formed in the trench with an insulator intervening, a first oxide film formed on the polysilicon so that the first oxide film is buried in the trench, a second oxide film formed on the first oxide film so that the second oxide film is buried in the trench, and a flowable insulator film formed on the second oxide film so that the flowable insulator film is buried in the trench.

A method of manufacturing a semiconductor apparatus includes forming a trench in a semiconductor layer, forming a gate electrode inside the trench, forming a thermally-oxidized film on the gate electrode inside the trench, forming a silicate glass film on the thermally-oxidized film inside the trench, forming a body region inside the semiconductor layer, and forming a source region on the body region. The method provides a semiconductor apparatus having reduced fluctuation of a channel length and low ON-resistance.

Method of manufacturing semiconductor apparatus

An epitaxial layer is formed on an n+ semiconductor substrate by epitaxial growth. A gate trench is formed to the surface of gate trench so that the bottom of gate trench reaches middle of the epitaxial layer. A gate insulator is formed on the inner wall of gate trench and a polysilicon is formed in the gate trench with the gate insulator interposed therebetween. An HTO film is formed on the surface of the polysilicon and the n&#x2212; epitaxial layer. At this time, an ion plantation is performed to the epitaxial layer through the HTO film. Hence, a p diffused base layer, an n+ diffused source layer, an n+ diffused source layer is formed. A CVD oxide film is formed on the HTO film. After a BPSG having flowability is deposited on the CVD oxide film, the BPSG film is planarized with a heat treatment of 900-1100 degree Celsius.

Growing community of inventors

Kanagawa, Japan

Yoshimitsu Murase