Anodic bonding of optical fibers-to-silicon for integrating MEMS devices and optical fibers

We present experimental details of anodic bonding of optical fibers to silicon wafers having conventional thickness using an ultra-thin silicon layer as a stress-reducing layer. These results are expected to play a significant role in integrating microelectromechanical systems (MEMS) devices with optical fibers to form a new class of devices. Tensile bond strength measurements are presented as a function of bonding temperature that indicate optimum temperatures for both the optical-fiber to silicon bonding and silicon-to-silicon bonding. These measurements indicate that the maximum average tensile strength of the fiber-to-silicon bonds is 4.25 MPa at 400 °C and the maximum average strength of the thick silicon-to-silicon bonds is 7.93 MPa at 350 °C. We also demonstrate the simultaneous anodic bonding of up to five layers of silicon, each 250 μm thick. A 2D ANSYS simulation reveals that ultra-thin silicon does play a role as a stress-reducing layer.