Patent ID: 11888078

Abstract:
A semiconductor photodiode (600) comprises a top side (602) with an active surface area (604) for light entry, a bottom side (606), a bulk structure (610) made of a single semiconductor material, the bulk structure comprising a p-type layer (612a) and an n-type layer (612b), which together form the p-n junction (612) of the photodiode, wherein one of the two layers of the p-n junction is an upper p-n junction layer (612a) and the other one is a lower p-n junction layer (612b), wherein the upper p-n junction layer (612a) is located proximate to the active surface area (604), and a semiconductor light absorption layer (614), wherein the light absorption layer (612a), (614) defines the active surface area (604) and is arranged on top of the bulk structure (610), above the upper p-n junction layer (612a), and the semiconductor material of the light absorption layer (614) is different from the semiconductor material of the bulk structure (610), the light absorption layer (614) and the upper p-n junction layer (612a) thus forming a heterojunction, and the photodiode (600) further comprises a precursor layer (620) arranged between the bulk structure (610) and the light absorption layer (614), the light absorption layer (614) being grown on the precursor layer.