Sodium distribution in thin-film anodic bonding

• Published in: Sensors and actuators. A, Physical Vol. 92; no. 1; pp. 223 - 228
• Main Authors: Visser, M.M., Weichel, S., Storås, P., de Reus, R., Hanneborg, A.B.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier B.V 01.08.2001; Elsevier Science
• Subjects: Anodic bonding; Applied sciences; EDX; Electronics; Exact sciences and technology; General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Lithography, masks and pattern transfer; Microelectronic fabrication (materials and surfaces technology); Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; SIMS; Sodium distribution; Thin-film; EDX; SIMS; Anodic bonding; Thin-film; Sodium distribution; Thin films; Wafer bonding; Energy dispersion; Sodium; Silicon oxides; Measurement sensor; Glass; Silicon nitrides; Anodized layers; X-ray spectroscopy; Experimental study
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/S0924-4247(01)00580-5

Depth profiles of the sodium distribution at bonded interfaces of silicon wafers, bonded with an intermediate borosilicate glass film, are recorded by secondary ion mass spectrometry (SIMS). A layer of dielectric material is present under the thin layer of glass, either a layer of silicon oxide or a combined layer of silicon oxide and silicon nitride. The glass layers are sputtered onto the wafers. Sodium is found to pile-up at interfaces. In the structures where a layer of silicon nitride is included, the amount of pile-up is reduced. Sputtered glass films are analysed with energy dispersive X-ray spectroscopy (EDX), and with a microprobe, in order to estimate the content of sodium in the films. Glass films deposited by e-beam evaporation are included in the EDX measurements for comparison purposes.