Photolithography for Minimal Fab System

Abstract

Minimal Fab System Photolithography has been developed for wafer patterning process without the requirement of a cleanroom. It consists of minimal resist coater, minimal maskless UV exposure, minimal mask aligner and minimal resist developer. We have proved in practice that the spin coating using minimal resist coater for a 0.5-inch wafer gives the identical result of resist thickness compared with 4-inch wafers without changes to a higher rotational speed. The minimal maskless UV exposure using Digital Light Processing (DLP) confirms that only one LED light source with the light intensity of 150 mW/cm 2 can expose over a 0.5-inch wafer in a few minutes. The minimal mask aligner is developed for a high speed exposure within 5-20 seconds. The aligner also uses a LED light source that can produce the light intensity of 14 mW/cm 2. The present photoresist resolution for the maskless UV exposure and the mask aligner are 1 µm and 2 µm, respectively. The minimal developer has minimized its consumption of developing agents. Due to the surface tension, a volume of developing agent is kept on the wafer surface for slowly spinning to stimulate the developing process. The developing time is 20% saved from that of the conventional puddle development.

Via Interconnections for Half-Inch Packaging of Electronic Devices Using Minimal Fab Process Tools

“…The process development of the laser-via introduced by Minimal Fab (MF) [27][28][29][30] is suitable for a low-volume production as shown in Fig. 1 (b) [31].…”

pH Sensing of Printed Flexible Sensors

“…The type of the processing materials depends on primarily on the fabrication technique and application of the sensors. Among the fabrication techniques, laser cutting technique [14] has been one of the options can be favored over the other fabrication techniques like screen printing [15], photolithography [16] and contact printing [17] due to their low cost and easy sample preparation, development of very flexible devices and large-scale production in a short time. This paper depicts the design and development of three flexible sensor prototypes that have been developed with different elastomers and conductive materials.…”

Development of Printed Sensors for Shoe Sensing Applications

“…have been used to develop the electrodes of the sensor. Similarly, different processing techniques like photolithography [11], screen printing [12], laser cutting [13] have been utilized to develop the sensors. The use of a particular technique depends on the resolution of the electrode and substrate thickness of the final sensor prototype.…”