A New Capacitive Displacement Sensor with High Accuracy and Long-Range",

ABSTRACT A new capacitive displacement sensor is designed and fabricated for measurement of a large displacement with very high accuracy. This sensor is a kind of linear encoder with an array of micro electrodes made by micromachining processes. The two patterned electrodes on the sensor substrates are assembled facing each other after being coated with thin dielectric film. Due to the thin dielectric film, it is highly sensitive to displacement but minimizes expected misalignments such as a tilting error. The sensor fabricated as a sample has a grating of electrodes with a width of 100µm, which is coated with a Diamond-Like Carbon(DLC) film 0.8 µm thick. The proposed sensor was tested to conclude that its resolution is 9.07 nanometers for the measuring range of 15 millimeters and that the linearity error is expected to be less than 0.02% throughout the measurable range

Deposition of Al Thin Film on Steel Substrate: The Role of Thickness on Crystallization and Grain Growth

In this study, we deposited aluminum (Al) films of different thicknesses on steel substrate and examined their phase, microstructure, and film growth process. We estimated that films of up to 30 nm thickness were mainly amorphous in nature. When the film thickness exceeded 30 nm, crystallization was observed. The further increase in film thickness triggered grain growth, and the formation of grains up to 40 nm occurred. In such cases, the Al film had a cross-grained structure with well-developed primary grains networks that were filled with small secondary grains. We demonstrated that the microstructure played a key role in optical properties. The films below 30 nm showed higher specular reflection, whereas thicker films showed higher diffuse reflections

Double-layered Ag-Al back reflector on stainless steel substrate for a Si:H thin film solar cells

An effective light trapping method for substrate-type hydrogenated amorphous silicon (a-Si:H) thin film solar cells is the use of a back reflector (BR) of high roughness, e.g., ‘hot silver’, which is deposited at temperatures higher than 450 °C. In this work, textured silver-aluminum (Ag–Al) BR films were fabricated by depositing Ag on Al film at Ag-deposition temperatures (TAg) ranging from 25 to 350 °C. The surface morphology and roughness of Ag–Al films were strongly affected by TAg. The Al and Ag films were formed entirely of Ag2Al alloy at TAg of 330 °C or higher, while the Ag–Al films maintained a double-layered structure at 290 °C or below. Although the films did not undergo alloying at TAg of 290 °C, the Ag–Al films have a well-developed surface structure with high diffuse-reflectance, compared to Ag films deposited at the same temperature. The conversion efficiency of an a-Si:H thin film solar cell on a flexible stainless steel substrate increased from 7.63% to 8.44% as TAg was increased from 25 to 290 °C, as a result of more effective light scattering by Ag–Al BRs, producing increased short-circuit current. However, at higher TAg, Ag2Al alloy films with sharp crystallite edges were formed, and were not appropriate as BRs. The present work clearly shows that double-layered Ag–Al films fabricated at temperatures as low as 290 °C could be useful back reflectors for substrate-type thin film solar cells

Double-layered Ag-Al back reflector on stainless steel substrate for a Si:H thin film solar cells

An effective light trapping method for substrate-type hydrogenated amorphous silicon (a-Si:H) thin film solar cells is the use of a back reflector (BR) of high roughness, e.g., ‘hot silver’, which is deposited at temperatures higher than 450 °C. In this work, textured silver-aluminum (Ag–Al) BR films were fabricated by depositing Ag on Al film at Ag-deposition temperatures (TAg) ranging from 25 to 350 °C. The surface morphology and roughness of Ag–Al films were strongly affected by TAg. The Al and Ag films were formed entirely of Ag2Al alloy at TAg of 330 °C or higher, while the Ag–Al films maintained a double-layered structure at 290 °C or below. Although the films did not undergo alloying at TAg of 290 °C, the Ag–Al films have a well-developed surface structure with high diffuse-reflectance, compared to Ag films deposited at the same temperature. The conversion efficiency of an a-Si:H thin film solar cell on a flexible stainless steel substrate increased from 7.63% to 8.44% as TAg was increased from 25 to 290 °C, as a result of more effective light scattering by Ag–Al BRs, producing increased short-circuit current. However, at higher TAg, Ag2Al alloy films with sharp crystallite edges were formed, and were not appropriate as BRs. The present work clearly shows that double-layered Ag–Al films fabricated at temperatures as low as 290 °C could be useful back reflectors for substrate-type thin film solar cells