Kabushiki Kaisha Toshiba

Yoshio Kasai

Akihito Yamamoto

Takashi Suzuki

Yuuichi Mikata

Hiroshi Akahori

Takanori Tsuda

Motoya Kishida

Miki Kawase

Hiroshi Ogino

A method of manufacturing a semiconductor device, which comprises forming a first semiconductor film on a surface of a semiconductor substrate, adsorbing a first impurity on a surface of the first semiconductor film, adsorbing a second impurity on the surface of the first semiconductor film, forming a second semiconductor film on the surface of the first semiconductor film, and solid-phase-diffusing the first impurity and the second impurity into a region of the semiconductor substrate which is located adjacent to the first and second semiconductor films to thereby form a first diffusion region containing the first impurity and a second diffusion region containing the second impurity, a concentration of the first impurity in the first diffusion region being higher than that of the second impurity in the second diffusion region, and the first diffusion region having the bottom thereof covered by the second diffusion region.

Method of manufacturing semiconductor device

A semiconductor wafer having an impurity diffusion layer formed in an inner surface of a trench is cleaned. The semiconductor wafer is inserted into a furnace, and NH,gas is introduced into the furnace in the low-pressure condition to create an atmosphere in which the temperature is set at 800&deg; C. to 1200&deg; C. and the partial pressures of H,O and O,are set at 1&times;10,Torr or less. A natural oxide film formed on the inner surface of the trench is removed, and substantially at the same time, a thermal nitride film is formed on the impurity diffusion layer. Then, a CVD silicon nitride film is formed on the thermal nitride film without exposing the thermal nitride film to the outside air in the same furnace. Next, a silicon oxide film is formed on the CVD nitride film. As a result, a composite insulative film formed of the thermal nitride film, CVD silicon nitride film and silicon oxide film is obtained. Then, an electrode for the composite insulative film is formed in the trench.

Semiconductor device applied to composite insulative film manufacturing method thereof

A semiconductor wafer having an impurity diffusion layer formed in an inner surface of a trench is cleaned. The semiconductor wafer is inserted into a furnace, and NH.sub.3 gas is introduced into the furnace in the low-pressure condition to create an atmosphere in which the temperature is set at 800.degree. C. to 1200.degree. C. and the partial pressures of H.sub.2 O and O.sub.2 are set at 1.times.10.sup.-4 Torr or less. A natural oxide film formed on the inner surface of the trench is removed, and substantially at the same time, a thermal nitride film is formed on the impurity diffusion layer. Then, a CVD silicon nitride film is formed on the thermal nitride film without exposing the thermal nitride film to the outside air in the same furnace. Next, a silicon oxide film is formed on the CVD nitride film. As a result, a composite insulative film formed of the thermal nitride film, CVD silicon nitride film and silicon oxide film is obtained. Then, an electrode for the composite insulative film is formed in the trench.

Semiconductor device applied to composite insulative film and

A semiconductor substrate is supported on a lower electrode provided within a chamber. The semiconductor substrate is heated up to about 600.degree. to 700.degree. by radiation heat from a halogen lamp. While the pressure within the chamber is reduced to about 0.1 to 1 Torr, the lower electrode is used as a positive electrode, and an upper electrode is used as a negative electrode. In this state, a DC voltage of 20 V is applied from a DC power supply. Then, a material gas is introduced into the chamber via an introducing hole, and a polysilicon film is grown on an oxide film on the semiconductor substrate. Electricity in the oxide film increases an initial growth rate of the polysilicon film and prevents formation of pinholes in the polysilicon film.

Growing community of inventors

Oita, Japan

Yoshio Kasai