本研究首次展示新型的串接式APD陣列，平衡了主動區尺寸、響應度與速度三者之間的性能衝突。我們所開發的覆晶封裝3×3陣列，其主動視窗尺寸為0.12 mm，能同時達成高響應度（1.2 A/W）、寬頻寬（6 GHz）與高增益頻寬積（GBP，150 GHz）的優異性能表現。 ;Enlarging the active window size of the photodetector (PD) while sustaining its high-speed and high-responsivity performances is the key to achieving a high-performance photo-receiver with a large field-of-view (FoV) angle for application in a free space laser communication system. However, in the traditional PD structure, a large active area always leads to a pronounced degradation in the RC-bandwidth. This problem has been overcome by using a tandem layout for high-speed p-i-n PD arrays. Such a structure though, sacrifices responsivity for high-speed and large FoV performance due to the requirements of current balancing between the different p-n junctions.
Here, for the first time, novel tandem APD arrays are demonstrated which relax the fundamental trade-offs among window size, responsivity, and speed. Our flip-chip packaged 3×3 arrays with a window size of 0.12 mm can simultaneously achieve a, high-responsivity (1.2 A/W), wide-bandwidth (6 GHz), and large GBP (150 GHz).
