6-axis force-torque sensor chip composed of 16 piezoresistive beams

This paper reports the design, a part of the fabrication process, especially ion doping method by oblique ion implantation, and experimental results of a 6-axis force-torque sensor chip composed of 16 piezoresistive beams. The sensor chip's area, 2mm square in size, is one-third of that of the minimum 6-axis sensor chip ever reported. It will enhance the mounting density of sensor array and also reduce the cost in case of volume production. These sensor chips were fabricated by MNOIC, 8-inch MEMS foundry in Japan, and their characteristic variations are enough small to make practical use of them.