Renesas Electronics Corporation

Photonics Electronics Technology Research Association

Nec Corporation

Shinichi Watanuki

Yasutaka Nakashiba

Masaru Wakabayashi

Hiroyuki Kunishima

Teruhiro Kuwajima

Tomoo Nakayama

Futoshi Komatsu

Tatsuya Usami

Yoshiaki Yamamoto

Takashi Ogura

Keiji Sakamoto

Atsuro Inada

Ken Ozawa

Tohru Kawai

Tsuyoshi Horikawa

Keizo Kinoshita

Tohru Mogami

Yoshihisa Matsubara

Takashi Ishigami

Yoshiaki Yamada

Tetsuya Iida

Shinichi Kuwabara

Akira Mitsuiki

Shigeaki Shimizu

Hiroyuki Okuaki

Shotaro Kudo

A semiconductor device includes: a semiconductor substrate; an insulating layer formed on the semiconductor substrate; an optical waveguide formed on the insulating layer, extending in a first direction in a plan view, and being made of silicon; and an interlayer insulating film formed on the insulating layer to cover the optical waveguide. In this case, a crystal surface of a side surface of the optical waveguide is a () surface.

Semiconductor device and method of manufacturing the same

A Semiconductor device includes an insulating layer, an optical waveguide, a first dummy semiconductor film, a second semiconductor film and a third semiconductor film. The optical waveguide is formed on the insulating layer. The first dummy semiconductor film is formed on the insulating layer and is spaced apart from the optical waveguide. The first dummy semiconductor film is formed on the first semiconductor film. The second semiconductor film is integrally formed with the optical waveguide as a single member on the insulating layer. The third semiconductor film is formed on the second semiconductor film. A material of the first dummy semiconductor film is different from a material of the optical waveguide. In plan view, a distance between the optical waveguide and the first dummy semiconductor film in a first direction perpendicular to an extending direction of the optical waveguide is greater than a thickness of the insulating layer.

Two optical waveguides and an insulating film provided to cover the optical waveguides are formed over an insulating layer. Two wirings and a heater metal wire are formed over the insulating film via an insulating film different from the above insulating film. The latter insulating film is thinner than the former insulating film, and has a higher refractive index than the former insulating film. The leaked light from either of the two optical waveguides can be suppressed or prevented from being reflected by any one of the two wirings, the heater metal wire, and the like to travel again toward the two optical waveguides by utilizing the difference between the refractive indices of the two insulating films.

Semiconductor device

A semiconductor device includes a substrate having a first surface and a second surface that have top and back relation, an insulating layer formed on the first surface of the substrate, and an optical waveguide formed on the insulating layer and formed of a semiconducting layer. A first opening is formed on the second surface of the substrate. The first opening overlaps the optical waveguide in plan view.

The semiconductor device has an optical waveguide formed on a substrate, a first conductor film formed in the same layer as the optical waveguide, an insulating film formed on the first conductor film, a second conductor film formed on the insulating film, and a first interlayer insulating film formed on the substrate so as to cover the optical waveguide and the second conductor film. The semiconductor device includes a first contact hole reaching the first conductor film, a second contact hole reaching the second conductor film, a first contact plug formed in the first contact hole, and a second contact plug formed in the second contact hole. The first conductor film is disposed between the first contact plugs and the board, but the second conductor film is not disposed between the first contact plugs and the board.

Semiconductor module, manufacturing method thereof, and communication method using the same

In order to improve the performance of a semiconductor device, a semiconductor layer EP is formed over a p-type semiconductor PR. An n-type semiconductor layer NRis formed over the semiconductor layer EP. The semiconductor layer PR, the semiconductor layer EP, and the semiconductor layer NRrespectively configure part of a photoreceiver. A cap layer of a material different from that of the semiconductor layer EP is formed over the semiconductor layer EP, and a silicide layer, which is a reaction product of a metal and the material included in the cap layer, is formed within the cap layer. A plug having a barrier metal film BMis formed over the cap layer through the silicide layer. Here, a reaction product of the metal and the material included in the semiconductor layer NRis not formed within the semiconductor layer NR

Semiconductor device and manufacturing method thereof

An optical waveguide formed at the same layer as that of a microscopic optical device and a spot size converter largely different in size are integrally formed. A semiconductor device has an optical waveguide part functioning as a spot size converter. The optical waveguide part includes a plurality of optical waveguide bodies penetrating through an interlayer insulation layer in the thickness direction.

An improvement is achieved in the reliability of a semiconductor device. Over an insulating layer, an optical waveguide and a p-type semiconductor portion are formed. Over the p-type semiconductor portion, a multi-layer body including an n-type semiconductor portion and a cap layer is formed. Over a first interlayer insulating film covering the optical waveguide, the p-type semiconductor portion, and the multi-layer body, a heater located over the optical waveguide is formed. In the first interlayer insulating film, first and second contact holes are formed. A first contact portion electrically coupled with the p-type semiconductor portion is formed continuously in the first contact hole and over the first interlayer insulating film. A second contact portion electrically coupled with the cap layer is formed continuously in the second contact hole and over the first interlayer insulating film. A wire formed over a second interlayer insulating film is electrically coupled with the heater and the first and second contact portions via plugs embedded in the second interlayer insulating film.

A low reflectance film with a second reflectance (50% or lower) lower than a first reflectance is formed between an optical directional coupler and a first-layer wiring with the first reflectance. Thus, even when the first-layer wiring is formed above the optical directional coupler, the influence of the light reflected by the first-layer wiring on the optical signal propagating through the first optical waveguide and the second optical waveguide of the optical directional coupler can be reduced. Accordingly, the first-layer wiring can be arranged above the optical directional coupler, and the restriction on the layout of the first-layer wiring is relaxed.

A semiconductor device including an optical waveguide and a p-type semiconductor portion is configured as follows. The optical waveguide includes: a first semiconductor layer formed on an insulating layer; an insulating layer formed on the first semiconductor layer; and a second semiconductor layer formed on the insulating layer. The p-type semiconductor portion includes the first semiconductor layer. The film thickness of the p-type semiconductor portion is smaller than that of the optical waveguide. By forming the insulating layer between the first semiconductor layer and the second semiconductor layer, control of the film thicknesses of the optical waveguide and the p-type semiconductor portion is facilitated. Specifically, when the unnecessary second semiconductor layer is removed by etching in a step of forming the p-type semiconductor portion, the insulating layer which is the lower layer functions as an etching stopper, and the film thickness of the p-type semiconductor portion can be easily adjusted.

In an optical waveguide section of an SIS type having a configuration of stacking a second semiconductor layer over a first semiconductor layer with a dielectric layer interposed, the first semiconductor layer is electrically coupled to a first electrode at a first lead-out section where the second semiconductor layer is not stacked. Further, the second semiconductor layer is electrically coupled to a second electrode at a second lead-out section not overlapping with the first semiconductor layer. As a result, when a contact hole for forming the second electrode is formed by dry etching, the dielectric layer between the first semiconductor layer and the second semiconductor layer is not damaged or broken and hence short-circuit failure between the first semiconductor layer and the second semiconductor layer can be prevented. The reliability of the optical waveguide section therefore can be improved.

The performances of a semiconductor device are improved. The semiconductor device includes an insulation layer, an optical waveguide part formed over the insulation layer, and including a p type semiconductor region and an n type semiconductor region formed therein, and an interlayer insulation film formed over the insulation layer in such a manner as to cover the optical waveguide part. At the first portion of the optical waveguide part, in a cross sectional view perpendicular to the direction of extension of the optical waveguide part, the n type semiconductor region is arranged at the central part of the optical waveguide part, and the p type semiconductor region is arranged in such a manner as to surround the entire circumference of the n type semiconductor region.

To achieve a high-reliability germanium photoreceiver. A photoreceiver portion of a germanium photoreceiver comprised of a p type silicon core layer, an i type germanium layer, and an n type silicon layer is covered with a second insulating film and from a coupling hole formed in the second insulating film, a portion of the upper surface of the photoreceiver portion is exposed. The coupling hole has, on the inner wall thereof, a barrier metal film and the barrier metal film has thereon a first-layer wiring made of a tungsten film. Tungsten hardly diffuses from the tungsten film into the i type germanium layer even when a thermal stress is applied, making it possible to prevent the resulting germanium photoreceiver from having diode characteristics deteriorated by the thermal stress.

Germanium-based photoreceiver having tungsten contacts

In a semiconductor device connected to a first optical waveguide, a phase modulation unit, and a second optical waveguide in this order and having an optical modulator guiding light in a first direction, the phase modulation unit includes: a semiconductor layer whose length in the first direction is larger than a width in a second direction orthogonal to the first direction and which is made of monocrystalline silicon; a core part serving as an optical waveguide region formed on the semiconductor layer, and extending in the first direction; a pair of slab parts arranged on both sides of the core part in the second direction; a first electrode coupled with one of the slab parts; and a second electrode coupled with the other of the slab parts. The core part has a p type semiconductor region and an n type semiconductor region extending in the first direction, and the second direction coincides with a crystal orientation &#x3c;100&#x3e; of the semiconductor layer.

Disclosed is an optical semiconductor device which can be improved in light shift precision and restrained from undergoing a loss in light transmission. In this device, an inner side-surface of a first optical coupling portion of an optical coupling region and an inner side-surface of a second optical coupling portion of the region are increased in line edge roughness. This manner makes light coupling ease from a first to second optical waveguide. By contrast, the following are decreased in line edge roughness: an outer side-surface of the first optical coupling portion of the optical coupling region; an outer side-surface of the second optical coupling portion of the region; two opposed side-surfaces of a portion of the first optical waveguide, the portion being any portion other than the region; and two opposed side-surfaces of a portion of the second optical waveguide, the portion being any portion other than the region.

Growing community of inventors

Ibaraki, Japan

Shinichi Watanuki