Oki Electric Industry Co., Ltd.

Oki Semiconductor Co., Ltd.

Naokatsu Ikegami

Norio Hirashita

Hidetsugu Uchida

Takasumi Kobayashi

Guo-lin Liu

Izumi Aikawa

The method of fabricating a semiconductor device includes subjecting a semiconductor substrate to trench etching by alternately repeating an etching step and a deposition step. The etching step creates a trench structure by dry-etching the exposed surface of the semiconductor substrate. An etching mask is formed on the surface of the semiconductor substrate so that the semiconductor substrate has the exposed portion. The deposition step deposits a protection film for suppressing etching of the trench side walls. The method of fabricating a semiconductor device also includes subjecting the semiconductor substrate that has just undergone the trench etching to a heat treatment at a predetermined temperature. The semiconductor substrate is heat-treated within a temperature range of 300 to 500&#xb0; C. immediately following the trench etching, for example. Plasma ashing is then performed.

Method of fabricating semiconductor device including forming a protective layer and removing after etching a trench

An acceleration sensor has a mass movably linked to a peripheral attachment section to which at least one stopper is attached to stop the motion of the mass in a certain direction. In the absence of acceleration, the mass rests at a distance from a first surface of the stopper. A quantity of a curable elastic adhesive on a second surface of the stopper absorbs impact of the mass on the first surface, enabling the acceleration sensor to survive mechanical shock. The curable elastic adhesive may adhere to the cover of a package in which the acceleration sensor is enclosed. The curable elastic adhesive may be applied as a drop or swath from a dispenser, which simplifies the manufacturing process and reduces the manufacturing cost.

Acceleration sensor manufacturable by simplified method

The present invention provides a method of manufacturing MEMS devices, comprising the steps of forming MEMS device bodies in a first substrate, defining concave portions around the MEMS device bodies over the first substrate, forming convex portions coincident with the concave portions in a second substrate, fitting the convex portions in the concave portions, respectively, to join the first substrate and the second substrate to each other, thereby forming a third substrate, sticking the third substrate to a UV sheet on the second substrate side, and dicing the third substrate to separate the MEMS device bodies from one another.

Method of manufacturing MEMS device

Micro-electrical-mechanical systems are fabricated in a substrate having a sacrificial layer sandwiched between two semiconductor layers. The semiconductor layers are selectively etched to create non-etched frames and etched microstructures immobilized within the frames by the sacrificial layer. An adhesive sheet is attached to one surface of the substrate, and the substrate is diced into chips, each including one frame and one immobilized microstructure. The sacrificial layer is then selectively etched to free a movable member in each microstructure. Finally, the chips are detached from the adhesive sheet, each chip becoming a micro-electrical-mechanical system. This fabrication method provides a simple and inexpensive way to avoid damage to the microstructure during the dicing process.

Method of manufacturing a micro-electrical-mechanical system

An accelerometer includes: a sensor chip including a weight portion for detecting a force imparted from outside, a frame portion that surrounds the weight portion, a beam portion that is deflectable and flexibly supports the weight portion, and a sensor element whose electric resistance varies depending on an amount by which the beam portion deflects; and a spacer provided at a position on a surface of a mounting substrate which position corresponds to the central portion of the weight portion. The sensor chip is mounted on the mounting substrate with a bottom surface of the frame portion being fixed at a predetermined position on the mounting substrate by an adhesive portion. The spacer has a thickness greater than that of the adhesive portion and may be formed by an adhesive concurrently with the adhesive portion, with a gap being maintained between the bottom surface of the weight portion and the spacer. The spacer serves to restrict an amount of downward movement of the weight portion which occurs when the beam portion deflects.

Accelerometer

Abstract of the Disclosure A method for manufacturing a semiconductor device including a conductive path extending from the upper surface of an insulating layer on a semiconductor substrate to a conductive member embedded in the insulating layer. An etching mask, which defines an etched hole for the conductor path, is formed on the insulating layer within a specified permissible error, and that portion of the insulating layer which is not covered by the etching mask is removed by a reactive ion etching unit having a reaction chamber into which a reactive gas of CHF/CO is introduced at a CHF/CO flow ratio of about 15/85. After this, the etched hole formed by an etching process is filled with a conductive material for the conductive path.

Method for manufacturing a semiconductor device

A method of manufacturing a semiconductor device includes the steps of, (1) preparing an SOI substrate, (2) forming a metal layer on the SOI substrate, (3) performing a first anneal treatment to the metal layer at a relatively low temperature in order to transform the metal layer to a first silicide layer, (4) forming an insulating layer on the first silicide layer, and (5) forming a contact hole, which reaches the first silicide layer, in the insulating layer; and (6) performing a second anneal treatment to the silicide layer at a relatively high temperature in order to transform the first silicide layer to a second silicide layer.

Method of manufacturing semiconductor device having thin film SOI structure

An acceleration sensor capable of standing a great acceleration is to be provided. It is configured of a mounting board and a sensor chip in which the sensor chip is formed of a weight, a beam and a frame. Then, the weight is surrounded by the frame. The weight is joined to the frame by a plurality of the beams, and the weight is separated from the board by being supported by the beams. Additionally, a thin, rectangular stopper is disposed on the mounting board right under the weight.

Acceleration sensor

A method for manufacturing a field effect transistor includes a first step for etching 70%&tilde;90% of the thickness of an insulating film (SiO or Si N ) formed covering a gate electrode formed on a silicon semiconductor substrate; and a second step for etching a remaining insulating film to remove an unnecessary portion, other than sidewall spacers, of the remaining insulating film. The two etching steps are respectively for the purpose of vertical processing of the sidewall spacers formed on each side of the gate electrode and securing a high etch selectivity ratio of the insulating film to the silicon substrate.

Method for manufacturing sidewall spacers of a semiconductor device with high etch selectivity and minimized shaving

When a via hole is formed in an insulating film formed by stacking a TEOS oxide film over an organic SOG film whose surface is modified as a low-K interlayer dielectric, by dry etching, a mixed gas of CHF3, CH2F2 and CO is used as an etching gas and a mixture ratio between CH2F2 and (CHF3&plus;CH2F2) is set to 50% or more, whereby the dry etching for the formation of the via hole is performed.

Method of forming via hole by dry etching

Disclosed herein is a via hole dry etching method using an organic SOG film as an interlayer dielectric having low-K. In the dry etching method, a mixed gas containing at least C4F8 and O2 is used as an etching gas and an O2/(C4F8&plus;O2) mixture ratio is set to 50% or less, thereby to carry out via hole dry etching. Further, the via hole dry etching is carried out by using a mixed gas containing at least CF4, CHF3 and N2 and setting the quantity of flow of N2 to above 10% and below 80% of the quantity of flow of CF4&plus;CHF3&plus;N2.

Method of dry etching organic SOG film

A method for forming a contact hole including forming a hole opening in a polysilicon film formed on an insulating film on the surface of a substrate; depositing a polysilicon film on the inner surface of the hole opening to make the diameter of the hole opening smaller; and carrying out dry etching to form an opening of the contact hole in the insulating film, using the polysilicon film as a mask. A gas mixture composed of CHF,and CO is used as an etching gas and a non-doped silicon oxide film is used as the insulating film.

Method for forming contact hole by dry etching

In order to achieve a method for analyzing the compositional distribution of deposited film adhering to the internal surface of a contact hole having a diameter in the deep submicron order, primary ions 18 are radiated into the surface 12a of an insulating film 12 where the contact hole 14 is formed to generate secondary ions 20. The primary ions are radiated into the surface of the insulating film from a constant diagonal direction. Then, mass spectrometry is performed on the resulting secondary ions to detect the compositional distribution of the deposited film 16 formed at the internal surface of the contact hole. Thus, the compositional distribution of the deposited film is ascertained over the depth-wise direction of the contact hole.

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Saitama, Japan

Naokatsu Ikegami