Precision in harsh environments

Abstract

Microsystems are increasingly being applied in harsh and/or inaccessible environments, but many markets expect the same level of functionality for long periods of time. Harsh environments cover areas that can be subjected to high temperature, (bio)-chemical and mechanical disturbances, electromagnetic noise, radiation, or high vacuum. In the field of actuators, the devices must maintain stringent accuracy specifications for displacement, force, and response times, among others. These new requirements present additional challenges in the compensation for or elimination of cross-sensitivities. Many state-of-the-art precision devices lose their precision and reliability when exposed to harsh environments. It is also important that advanced sensor and actuator systems maintain maximum autonomy such that the devices can operate independently with low maintenance. The next-generation microsystems will be deployed in remote and/or inaccessible and harsh environments that present many challenges to sensor design, materials, device functionality, and packaging. All of these aspects of integrated sensors and actuator microsystems require a multidisciplinary approach to overcome these challenges. The main areas of importance are in the fields of materials science, micro/nano-fabrication technology, device design, circuitry and systems, (first-level) packaging, and measurement strategy. This study examines the challenges presented by harsh environments and investigates the required approaches. Examples of successful devices are also given.

Soft Microreactors for the Deposition of Conductive Metallic Traces on Planar, Embossed, and Curved Surfaces

“…We further determined the deposition rate, the chemical stability under ambient conditions, and the adhesion characteristics of the traces generated using μ‐DECD. We measured the deposition rate, using profilometry and confocal microscopy (Figure e), of the process by examining the thickness of traces generated for different deposition times (between 4 and 60 min) and found a rate of 6.7 ± 1.6 µm h −1 (giving traces which ranged in thickness from 1 to 5 µm), which is comparable to the current strategies used for fabricating conductive traces on nonplanar objects (e.g., laser directed structuring), or conductive traces in general (e.g., sputtering, thermal evaporation, atomic layer deposition) . Higher deposition rates can be achieved by modifying the deposition bath composition, or using electroplating to increase the thickness of a thin conductive trace deposited via ECD (a common strategy used in the fabrication of PCBs) .…”

New development of atomic layer deposition: processes, methods and applications

“…In the industry, the PVD and CVD have been the popular deposition methods, however, ALD has been recognized as the leading emerging technology as nanometre-size layer thickness or pinhole free layers are becoming more important [54].…”

Special Issue: “Coatings for Harsh Environments”

“…Harsh environments cover areas such as high-and low-temperature, (bio)-chemical and mechanical disturbances (including extreme stresses and stress cycles), electromagnetic noise, pressure, radiation, or vacuum [3]. These environments by their very nature challenge the ability of materials to function.…”

“…Humans were able to use materials in extreme environments never before envisaged to be accessible by developing "engineered" coatings. These extreme environments are often called "harsh" environments.Harsh environments cover areas such as high-and low-temperature, (bio)-chemical and mechanical disturbances (including extreme stresses and stress cycles), electromagnetic noise, pressure, radiation, or vacuum [3]. These environments by their very nature challenge the ability of materials to function.…”