Back-illuminated photodetector

Abstract

An n-type contact layer (2), a p-type light-doped light absorption layer (3), an n-type light-doped light absorption layer (4), and a window layer (5) are layered in said order on a substrate (1). A p-type region (7) is formed in a portion of the window layer (5) and the n-type light-doped light absorption layer (4).

Claims

1. circuit board and An n-type contact layer, a p-type light-doped light-absorbing layer, an n-type light-doped light-absorbing layer, and a window layer are sequentially stacked on the substrate. The window layer and a p-type region formed in a part of the n-type light-doped light-absorbing layer are provided, The p-type light-doped light-absorbing layer and the n-type light-doped light-absorbing layer are formed from a semiconductor material having a band gap that absorbs incident light. A back-side incident photodetector characterized in that the band gap energy of the p-type light-doped light-absorbing layer is greater than the band gap energy of the n-type light-doped light-absorbing layer.

2. A substrate and An n-type contact layer, a p-type light-doped light-absorbing layer, an n-type light-doped light-absorbing layer, and a window layer are sequentially stacked on the substrate. A p-type region formed in the window layer and a part of the n-type light-doped light-absorbing layer, An n-type electron transport layer is inserted between the n-type contact layer and the p-type light-doped light-absorbing layer, A back-side incident photodetector is characterized by comprising an n-type doped layer, which is inserted between the n-type electron transport layer and the p-type light-doped light-absorbing layer and has a higher impurity concentration than the n-type electron transport layer.

3. A substrate and An n-type contact layer, a p-type light-doped light-absorbing layer, an n-type light-doped light-absorbing layer, and a window layer are sequentially stacked on the substrate. The window layer and a p-type region formed in a part of the n-type light-doped light-absorbing layer are provided, In a plan view, a trench is formed outside the p-type region from the window layer to the layer below the p-type light-doped light-absorbing layer. A back-side incident photodetector characterized in that the impurity concentration in the outer peripheral portion of the p-type light-doped light-absorbing layer in contact with the trench is lower than the impurity concentration in the central portion of the p-type light-doped light-absorbing layer.

4. The impurity concentrations of the p-type light-doped light-absorbing layer and the n-type light-doped light-absorbing layer are 5 × 10 １７ cm －３ The back-surface incident light-receiving element according to any one of claims 1 to 3, characterized in that it is as follows:

5. The impurity concentration of the aforementioned p-type light-doped light-absorbing layer is 1 × 10⁻⁶ １７ cm －３ The back-side incident light-receiving element according to claim 4, characterized in that it is as follows.

6. The back-side incident light-receiving element according to any one of claims 1 to 3, characterized in that the thickness of the n-type light-doped light-absorbing layer is 0.3 μm or more.

7. The back-side-incident light-receiving element according to claim 2 or 3, characterized in that the p-type light-doped light-absorbing layer and the n-type light-doped light-absorbing layer are formed of the same semiconductor material having a band gap that absorbs incident light.

8. circuit board and An n-type contact layer, a first n-type light-doped light-absorbing layer, a p-type doped light-absorbing layer, a second n-type light-doped light-absorbing layer, and a window layer are sequentially laminated on the substrate. The window layer and the p-type region formed in a part of the second n-type light-doped light-absorbing layer are provided. A back-surface incident light-receiving element characterized in that the impurity concentration of the p-type doped light-absorbing layer is 5 × 10¹⁷ cm⁻³ or more.

9. The impurity concentrations of the first n-type light-doped light-absorbing layer and the second n-type light-doped light-absorbing layer are 5 × 10⁻¹⁰. １７ cm －３ The back-side incident light-receiving element according to claim 8, characterized in that it is as follows:

10. The back-side-entry photodetector according to claim 8 or 9, characterized in that the first n-type light-doped light-absorbing layer, the p-type light-absorbing layer, and the second n-type light-doped light-absorbing layer are formed of the same semiconductor material having a band gap that absorbs incident light.

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