GIGAHERTZ ULTRASONIC MULTI-IMAGING OF SOIL TEMPERATURE, MORPHOLOGY, MOISTURE, AND NEMATODES

This work reports a single chip GHz ultrasonic micro-imager for imaging soil temperature, morphology, moisture, and pests such as nematodes. A 128x128 pixel array of 50x50 mu m piezoelectric Aluminum Nitride (AlN) transducers is integrated onto 130nm CMOS substrates. The imager-surface is segmented into three sensing regions: soil temperature, moisture, and direct soil imaging of morphology and pest, such as nematodes. The imager's compact size and potentially low price can significantly reduce the barrier to the success of digital agriculture, which requires data collections over millions of acres in a cost-effective way with high sampling resolution.