en 2-Optoelectronics and Photonics Optoelectronics and Photonics Research Paper Research Paper <div style="text-align: justify;">A model of a low noise high quantum efficiency n⁺np Germanium Photodiode utilizing ion implantation technique and subsequent drive-in diffusion in the n layer is presented. Numerical analysis is used to study the influence of junction depth and bulk concentration on the electric field profile and quantum efficiency. The performance of the device is theoretically treated especially at the wave-length region 1.55&mu;m where the Silica optical fiber has minimum attenuation loss. It has been found that at this wave-length and for the optimum device design the quantum efficiency approaches about 90%.</div> Avalanche Photodiodes,Responsivity,Quantum Efficiency, 509 515 http://ijeee.iust.ac.ir/browse.php?a_code=A-10-2692-1&slc_lang=en&sid=1 T. Baldawi thbaldawi@asu.edu.jo 180031947532846008294 180031947532846008294 No Department of Electrical Engineering, Princess Sumaya University for Technology, Amman, Jordan. A. Abuelhaija a_abualhijaa@asu.edu.jo 180031947532846008295 180031947532846008295 Yes Electrical Engineering Department, Applied Science Private University, Amman, Jordan.