Fabrication of optical transmission elements in an SiNx membrane

✍ Scribed by Chien Chieh Lee; Yu Cheng Chang; Jenq Yang Chang; Chien Feng Chiu; Guo Chung Chi

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 505 KB
• Volume: 69
• Category: Article
• ISSN: 0167-9317
• DOI: 10.1016/s0167-9317(03)00223-5

✦ Synopsis

This paper presents a method for the fabrication of silicon-based optical elements in an SiN membrane. This x device will transmit visible and infrared light, and can be used for various types of optical elements, such as gratings, lenses, diffractive optical elements (DOEs), etc. This is a new designed structure for fabricating optical transmission elements. Since the fabrication processes are based on silicon micromachining technology, they can be easily incorporated with other active optical components in microoptoelectromechanical systems (MOEMS). An SiN film is deposited by low-pressure chemical vapor deposition (LPCVD) and the free-standing membrane x is formed by KOH silicon backside etching, from which substrate materials are removed. A transmission grating and Fresnel lens have been produced from this membrane. Scanning electron microscopic (SEM) images and the optical characteristics of the transmission grating are shown.