Next Article in Journal
A New Analytical Model to Estimate the Voltage Value and Position of the Pull-In Limit of a MEMS Cantilever
Next Article in Special Issue
A One-Square-Millimeter Compact Hollow Structure for Microfluidic Pumping on an All-Glass Chip
Previous Article in Journal
Microfluidic Device to Measure the Speed of C. elegans Using the Resistance Change of the Flexible Electrode
Previous Article in Special Issue
Surface Free Energy Determination of APEX Photosensitive Glass
Article Menu

Export Article

Open AccessArticle
Micromachines 2016, 7(3), 51;

An Investigation of Processes for Glass Micromachining

Microsystem Integration Center (μSIC), Tohoku University, Sendai 980-8579, Japan
Graduate School of Engineering, Tohoku University, Sendai 980-8579, Japan
Author to whom correspondence should be addressed.
Academic Editor: Rolf Wuthrich
Received: 15 February 2016 / Revised: 11 March 2016 / Accepted: 14 March 2016 / Published: 22 March 2016
(This article belongs to the Special Issue Glass Micromachining)
Full-Text   |   PDF [7367 KB, uploaded 22 March 2016]   |  


This paper presents processes for glass micromachining, including sandblast, wet etching, reactive ion etching (RIE), and glass reflow techniques. The advantages as well as disadvantages of each method are presented and discussed in light of the experiments. Sandblast and wet etching techniques are simple processes but face difficulties in small and high-aspect-ratio structures. A sandblasted 2 cm × 2 cm Tempax glass wafer with an etching depth of approximately 150 µm is demonstrated. The Tempax glass structure with an etching depth and sides of approximately 20 μm was observed via the wet etching process. The most important aspect of this work was to develop RIE and glass reflow techniques. The current challenges of these methods are addressed here. Deep Tempax glass pillars having a smooth surface, vertical shapes, and a high aspect ratio of 10 with 1-μm-diameter glass pillars, a 2-μm pitch, and a 10-μm etched depth were achieved via the RIE technique. Through-silicon wafer interconnects, embedded inside the Tempax glass, are successfully demonstrated via the glass reflow technique. Glass reflow into large cavities (larger than 100 μm), a micro-trench (0.8-μm wide trench), and a micro-capillary (1-μm diameter) are investigated. An additional optimization of process flow was performed for glass penetration into micro-scale patterns. View Full-Text
Keywords: glass micromachining; wet etching; sandblast; reactive ion etching; glass reflow process glass micromachining; wet etching; sandblast; reactive ion etching; glass reflow process

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Van Toan, N.; Toda, M.; Ono, T. An Investigation of Processes for Glass Micromachining. Micromachines 2016, 7, 51.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Micromachines EISSN 2072-666X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top