Microsystems and Microfabrication for a Sustainable World

The IC industry can have a definitive impact on the environment based on the extent of sustainability practices incorporated in manufacturing. Automobiles, personal devices, smart homes, medical implants, data centers, and IoT sensors' explosion continue to increase the electronics content of the world. The proliferation of electronics production impacts the environment by increasing the carbon footprint of semiconductor production and end-of-life processing of electronics. As the volume of silicon and flexible electronics continues to rise, the semiconductor industry's impact on the environment, especially near the production facilities, is essential and must be highly sustainable. While the environmental impact of the semiconductor industry is important, the net effect of semiconductors is dwarfed by that of the energy, agriculture, and transportation sectors of the economy. In this view, it is important for microsystems to help reduce the impact of these sectors. This talk will focus on approaches where electronics production and electronics can lead to a more sustainable world with a three-pronged approach – AI-based optimization of semiconductor manufacturing, a novel ultrasonic sensor technology for soil and environmental imaging, and minimized end-of-life electronic waste by means of polymer-based vanishing electronics. Semiconductor electronics can play a crucial role in making farming, transportation, and construction more sustainable. It is essential to implement manufacturing practices such that the overall impact on the environment, carbon emission footprint, water usage, waste production is reduced to make a sustainable pathway to the continued growth of electronics. One aspect of process optimization is through the identification of time-varying system parameters that affect resource usage. For example, as yield reduces over time, its root cause can be hard to determine due to the equipment's complex interdependencies. Two vital processes that control device yield and resource usage are lithography and plasma etching and deposition. This paper will explore new sensors and pathways to reduce the resources needed to operate lithography and plasma systems. Firstly, the IC production process itself consumes energy, water, and uses chemicals that contribute to the carbon and chemical footprint. The use of the resources can be optimized by implementing new AI-based process monitoring and optimization. In this approach, we add environmental impact as an additional parameter to be optimized. Second, to monitor water, pesticide, and fertilizer usage in agriculture, we report on a novel sensor technology that can serve to feedback control agriculture with an environmental impact as a key parameter thereby minimizing carbon footprint for the sensor node. A soil-based imager technology using ultrasonic beams integrated with CMOS on flexible substrates has been used to measure water motion, chemistry, and insect motion in soil. Thirdly, we report on the use of vanishing electronics based on new polymers that can be vaporized using heat, potentially eliminating the long-term silicon waste accumulation caused by electronics. These examples highlight a new approach to incorporate sustainability in electronics micro-engineering.