| 摘要 |
PURPOSE:To make a photosensitivity distribution uniform by a method wherein a specific light absorbing layer, 1st 4-element layer and mesa-shape 2nd 4-ele ment layer are formed on an InP substrate in this order respectively and the mesa-shape 2nd 4-element layer is buried in an n-type InP and a p-n junction is formed in the 2nd 4 element layer. CONSTITUTION:InP of a buffer layer, In0.53Ga0.47As 2, In0.31Ga0.69As0.66P0.34 3 and In0.97Ga0.03As0.06P0.94 14 are made to grow on an InP substrate 1 by liquid phase growth. Then mesa-etching is carried out with an insulating film (nitride film) 8 as a mask and InP 15 is made to grow by liquid phase growth along the mesa-shape. A nitride film 9 with a window is applied to the wafer formed like this and a diffused layer 6 is formed by diffusion of Cd to form a p-n junction. Besides, a guard ring part is ion-implanted with Be to form a graded junction part 7. With this constitution, an avalanche photodiode which provides a uniform photosensitivity distribution of the photodetecting plane can be obtained. |
