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This paper reports a CMOS-integrated three-axial force sensor system realized using a post-CMOS compatible low-temperature fabrication process which allows to process single IC dies as obtained from multi-project wafer (MPW) runs. The sensor system can be applied in coordinate measurement machines used for three-dimensional metrology of microcomponents. It is based on a flexible micromechanical cross structure suspended through thin silicon membrane hinges in a silicon frame. The cross is realized using double-sided deep reactive ion etching of IC chips comprising field effect transistor based piezoresistive stress sensor elements integrated with on-chip circuitry. The sensor elements are located on the membrane hinges and detect the deformations of the cross structure upon forces applied to a tactile element. The sensor system is able to monitor out-of-plane deflections of the cross structure with a resolution of 33 nm.

This paper presents a handheld microsystem that uses discharge spectroscopy to analyze chemicals both in vapor and liquid phases. The system employs a battery-operated circuit and interface for generating the microdischarge and performing the analysis. It uses swappable liquid and gas discharge microchips, which interface to the common platform. A pump and inert carrier gases are not utilized.

During x-ray exposure in the LIGA process, the polymethylmethacrylate (PMMA) photoresist undergoes chain scission, which reduces the molecular weight of the exposed materials. Under some exposure and development conditions, sidewall cracking is observed on the PMMA sidewall, creating surface texture that is undesirable. In this research, exposed and developed PMMA sidewalls were examined for evidence of crack formation using optical profilometry. PMMA thickness, exposure dose and delay time between the end of exposure and beginning of development were varied. Our analysis of samples, with three different radiation doses and four different delay times from the end of exposure to the beginning of development, indicate that the first occurrence of cracking and the extent of cracking are affected by both the dose and the development delay time. This work includes the examination of the depth of cracks into the PMMA, distance between cracks, the width of cracks and the relationship between crack occurrence and dose profile. An empirical predictive model to correlate the delay time to the observance of sidewall cracking based on the deposited dose is presented. This information has direct implication for predicting processing conditions and logistics for LIGA fabricated parts.