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This paper aims to develop an ideal technique for the preparation of print circuit boards (PCBs) with ladder conductive lines on practical industrial process lines.

First, the raw materials of ladder copper-clad laminates were prepared by plating double-sided copper-clad laminates with vertical plating line. Second, etching compensation experiments were designed and conducted to set up the relationships between etching compensation and width of conductive lines on ladder line print circuit boards (LLPCBs). Third, to evaluate the process technique for the preparation of LLPCBs through etching compensation, verification experiments were designed and conducted on a practical industrial process line, and the quality of lines on LLPCBs was observed and evaluated.

Under the judgment of the quality of conductive lines on LLPCBs as well as the feasibility with a practical industrial process line, the process technique for the preparation of LLPCBs with etching compensation is a simple and reliable method which has the potential to be applied in the industry.

It is the first successful report of a new method that produces LLPCBs with etching compensation and has the potential to be applied in the industry.

Printed (circuit) boards have been used in the electronics industry for the past 25 years and more. The technology used to design and manufacture PCBs is well known and accepted. Recently, however, designers of electronic equipment have shown that the use of newer materials and systems, such as flexible and moulded circuits, hybrid circuits, or a combination of these, can significantly improve the cost/performance ratio for electronic interconnects. This paper examines some of the many possibilities open to electronics designers and how these new opportunities can improve the economics and performance of electronic equipment.

The purpose of this study is to present the state of the art for fiber Bragg grating (FBG) acceleration sensing technologies from two aspects: the principle of the measurement dimension and the principle of the sensing configuration. Some commercial sensors have also been introduced and future work in this field has also been discussed. This paper could provide an important reference for the research community.

This review is to present the state of the art for FBG acceleration sensing technologies from two aspects: the principle of the measurement dimension (one-dimension and multi-dimension) and the principle of the sensing configuration (beam type, radial vibration type, axial vibration type and other composite structures).

The current research on developing FBG acceleration sensors is mainly focused on the sensing method, the construction and design of the elastic structure and the design of a new information detection method. This paper hypothesizes that in the future, the following research trends will be strengthened: common single-mode fiber grating of the low cost and high utilization rate; high sensitivity and strength special fiber grating; multi-core fiber grating for measuring single-parameter multi-dimensional information or multi-parameter information; demodulating equipment of low cost, small volume and high sampling frequency.

The principle of the measurement dimension and principle of the sensing configuration for FBG acceleration sensors have been introduced, which could provide an important reference for the research community.

ISHM‐Benelux held its 1987 Autumn Conference on 29 October, at the Antwerp Crest Hotel. This one‐day meeting focused on applications of hybrid circuit technology in various fields of electronic and related industries.

The purpose of this paper is to describe the fabrication of a miniaturized membrane type double cavity vacuum‐sealed micro sensor for absolute pressure using front‐side lateral etching technology.

Potassium hydroxide‐based anisotropic etching of single crystal silicon is used to realize the cavities under the membrane type diaphragms through channels on the sides. The diaphragms consist of composite layers of plasma‐enhanced chemical vapour deposition (PECVD) of silicon nitride and silicon dioxide. PECVD of silicon dioxide is done for sealing the channels and the cavity in vacuum. Boron thermal diffusion in low‐pressure chemical vapour deposition of polysilicon layer over the membrane is done for realizing resistors. The fabricated device uses Wheatstone half bridge circuit to read the variation of resistance with respect to an applied pressure.

A double cavity vacuum‐sealed absolute pressure micro sensor has been fabricated successfully using front‐side lateral etching technology and has been measured for pressure range of 0‐0.45 MPa. The measured pressure sensitivity of two pressure sensors is 9.28 and 10.44 mV/MPa.

The paper shows that front‐side lateral etching technology is feasible in the fabrication of small vacuum‐sealed cavities and absolute pressure sensors.

The aim of this paper is to provide a new wafer prealigning robot for the photo‐etching facility during the manufacturing of IC products.

The shape center is measured by a reflection‐style laser sensor in the wafer's radial direction, and the position is measured by a penetration‐style laser sensor. A dynamic error compensation is applied to eliminate the radial runout and wobble of the rotary stage, which have effects on the measurement of the wafer's shape center.

It is found that the new wafer prealigning robot can satisfy the accuracy requirement.

The robot requires that the shape center can be accurately calculated.

The robot is applicable to wafer prealigning for the photo‐etching facility.

A wafer prealigning robot based on the shape center calculation method has been developed and is described in the paper.

Reports the design, fabrication and packaging of a micromachined silicon/Pyrex based chip for the polymerase chain reaction (PCR). The anodic bonding method is used for sealing the chambers of 1μl volume with a Pyrex glass wafer. Platinum resistors on the back of the wafer are used as heaters and temperature sensors. The chip is externally cooled by forced air to achieve rapid temperature cycling. The transparency of the Pyrex makes it possible for using optical readout methods. The packaging is especially designed for easy handling, filling, power connection, temperature regulation and optical readout. The mass production of such silicon reactors could make single‐shot throwaway devices economically viable.

To present an update and the latest results from work on a project aimed at enabling printed circuit board (PCB) manufacturing to reduce the effect upon production yields by material distortions during the manufacturing process.

Measurement data was collated from inspection steps within the PCB manufacturing process and analysed to provide data describing the distortions of materials used. The data was used to generate a self‐learning model which can be used to predict material movement prior to manufacture.

The data collated enabled CAM engineers at the design introduction stage to model the PCB build and simulate the material movement that will take place during the manufacturing processes. With this knowledge, the correct compensations to counter the material movement can be applied to the production tooling, eliminating the need to run manufacturing test batches.

The technology has been used to ensure inner‐layer designs with nominal dimensions after the lamination stage. Further, development work should be undertaken to collate measured data from other parts of the PCB manufacturing process and model the material movement around all registration critical processes.

The paper details how data collated by production processes can be utilised to train mathematical models and provide modified‐tooling information to increase yields in the manufacturing process.