Investigation of geometric parameters of silicon structures in device layer during manufacture of sensitive elements of micromechanical accelerometers
Year: 2025
Type: article
Abstract: The technological processes of fabrication inertial elements of devices of microelectromechanical systems are investigated. The influence of etch square on critical parameters of the process of deep reactive ion etching, allowing to etch silicon structures with high aspect ratios for fabrication micromechanical accelerometers and gyroscopes, is studied. Inertial sensitive elements of micromechanical accelerometers were manufactured on a 150 mm wafer diameter within the framework of an advanced technological process with minimized square etch area on stage of formation of the device layer consisting of an inertial mass, an elastic suspension, control and measuring electrodes, and insulating frame. Values of geometric parameters of silicon structural layers of the device were obtained by analyzing the profiles of inertial visible elements on a scanning electron microscope. Elements of device layer were studied both in the radial and tangential directions of a substrate with a diameter of 150 mm to determine the spread of geometric parameters of inertial sensitive elements. The technological process of fabrication inertial sensitive elements to reduce square of etch area at the stage of device layer formation using an alternative opening the area of the contacts is shown. Based on measurements of the geometric parameters of the silicon structures of the device layer, it was found that the dimensions of the elements and their deviations change in the radial direction from the center of the substrate to the edge. The spread of the geometric parameters of the silicon structures of inertial sensitive elements manufactured according to the advanced technological process on a 150 mm diameter substrate was reduced to 0.4 μm, and the spread of their deviations was reduced to 0.2 μm. The proposed technological process can be used to increase the yield of devices goods during manufacture of inertial sensitive elements and to obtain more uniform characteristics of microelectromechanical systems, such as accelerometers and gyroscopes. The work results can be used in the design of technological processes for the manufacture of new inertial sensitive elements.
Author: N. S. Karanin
Institution: ITMO University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4409806055