Semiconductor Energy Laboratory Co., Ltd.

Erika Kato

Tetsuhiro Tanaka

Hidekazu Miyairi

Ryota Tajima

Mitsuhiro Ichijo

Kazutaka Kuriki

Toshiyuki Isa

Takashi Ohtsuki

Ryo Tokumaru

Tomokazu Yokoi

Miyako Nakajima

Kunihiko Suzuki

Yasuhiro Jinbo

Yuji Egi

Ryu Komatsu

Miyako Morikubo

Takashi Ienaga

A method for forming an amorphous semiconductor which contains an impurity element and has low resistivity and a method for manufacturing a semiconductor device with excellent electrical characteristics with high yield are provided. In the method for forming an amorphous semiconductor containing an impurity element, which utilizes a plasma CVD method, pulse-modulated discharge inception voltage is applied to electrodes under the pressure and electrode distance with which the minimum discharge inception voltage according to Paschen's Law can be obtained, whereby the amorphous semiconductor which contains an impurity element and has low resistivity is formed.

Manufacturing method of semiconductor film, manufacturing method of semiconductor device, and manufacturing method of photoelectric conversion device

An embodiment of the present invention is a microcrystalline semiconductor film having a thickness of more than or equal to 70 nm and less than or equal to 100 nm and including a crystal grain partly projecting from a surface of the microcrystalline semiconductor film. The crystal grain has an orientation plane and includes a crystallite having a size of 13 nm or more. Further, the film density of the microcrystalline semiconductor film is higher than or equal to 2.25 g/cmand lower than or equal to 2.35 g/cm, preferably higher than or equal to 2.30 g/cmand lower than or equal to 2.33 g/cm.

Microcrystalline semiconductor film, method for manufacturing the same, and method for manufacturing semiconductor device

A thin film transistor in which deterioration at initial operation is not likely to be caused and a manufacturing method thereof. A transistor which includes a gate insulating layer at least whose uppermost surface is a silicon nitride layer, a semiconductor layer over the gate insulating layer, and a buffer layer over the semiconductor layer and in which the concentration of nitrogen in the vicinity of an interface between the semiconductor layer and the gate insulating layer, which is in the semiconductor layer is lower than that of the buffer layer and other parts of the semiconductor layer. Such a thin film transistor can be manufactured by exposing the gate insulating layer to an air atmosphere and performing plasma treatment on the gate insulating layer before the semiconductor layer is formed.

Thin film transistor including silicon nitride layer and manufacturing method thereof

An object is to provide a thin film transistor with small off current, large on current, and high field-effect mobility. A silicon nitride layer and a silicon oxide layer which is formed by oxidizing the silicon nitride layer are stacked as a gate insulating layer, and crystals grow from an interface of the silicon oxide layer of the gate insulating layer to form a microcrystalline semiconductor layer; thus, an inverted staggered thin film transistor is manufactured. Since crystals grow from the gate insulating layer, the thin film transistor can have a high crystallinity, large on current, and high field-effect mobility. In addition, a buffer layer is provided to reduce off current.

Thin film transistor and method for manufacturing the same

A seed crystal including mixed phase grains having high crystallinity with a low grain density is formed under a first condition, and a microcrystalline semiconductor film is formed over the seed crystal under a second condition which allows the mixed phase grains in the seed crystal to grow to fill a space between the mixed phase grains. In the first condition, the flow rate of hydrogen is 50 times or greater and 1000 times or less that of a deposition gas containing silicon or germanium, and the pressure in a process chamber is greater than 1333 Pa and 13332 Pa or less. In the second condition, the flow rate of hydrogen is 100 times or greater and 2000 times or less that of a deposition gas containing silicon or germanium, and the pressure in the process chamber is 1333 Pa or greater and 13332 Pa or less.

Method for forming microcrystalline semiconductor film and method for manufacturing semiconductor device

A microcrystalline semiconductor film is formed over a substrate using a plasma CVD apparatus which includes a reaction chamber in such a manner that a deposition gas and hydrogen are supplied to the reaction chamber in which the substrate is set between a first electrode and a second electrode; and plasma is generated in the reaction chamber by supplying high-frequency power to the first electrode. Note that the plasma density in a region overlapping with an end portion of the substrate in a region where the plasma is generated is set to be higher than that in a region which is positioned more on the inside than the region overlapping with the end portion of the substrate, so that the microcrystalline semiconductor film is formed over a region which is positioned more on the inside than the end portion of the substrate.

Method for forming semiconductor film and method for manufacturing semiconductor device

Growing community of inventors

Kanagawa, Japan

Erika Kato