STM Article Repository

In the present era of big data and 5G wireless, both microelectronic and photonic components are indispensable building blocks. For microelectronics, device miniaturization has been following Moore’s law to attain higher speed and greater functionality. For photonics, similar device scaling is also evolving in both lasers and photodiodes to transmit high data rates of 25 Gb/s and beyond. However, such device miniaturization may impose challenges such as reliability and fabrication that require careful scientific and engineering studies. In particular, the reliability understanding of photonic device scaling is fairly rudimentary with only scattered reports. In this paper, we study the device and reliability scaling of nanoscale avalanche photodiodes (APDs). The device miniaturization of APDs mainly involves thickness reduction in the charge control and multiplication layers. The layer reduction however causes an increase in breakdown field that may adversely affect reliability in several aspects such as electrical/optical overload and electrostatic discharge (ESD). We present a new reliability degradation model of APDs based on the breakdown field and correlate it with the experimental data. Empirical reliability equations are instituted to establish quantitative formulation. We discuss the overload and ESD performances as a function of breakdown field for both planar-type and mesa-type APD structures.