Abstract: A device includes a first integrated circuit containing a photodiode and a first metal interconnect structure connected to the photodiode, and a second integrated circuit containing a transistor and a second metal interconnect structure connected to the transistor. The first integrated circuit and the second integrated circuit are connected together through the first metal interconnect structure and the second metal interconnect structure. Since no transistor is present around the photodiode, the photodiode has an increased photosensitive area and an improved fill factor, resulting in an increase of the quantum efficiency, higher integration and lower consumption of the image sensor.

Abstract: A method of selectively etching a semiconductor device and manufacturing a BSI image sensor device includes etching a doped silicon substrate with an HNA solution for a predetermined time duration to obtain an etching solution having a concentration C1 of nitrite ions, etching the semiconductor device using the obtained etching solution. Etching the semiconductor device requires an initial concentration C0 of nitride ions that is lower than C1. The HNA solution comprises a hydrofluoric acid (HF), a nitric acid (HNO3), and a acetic acid (CH3COOH). The BSI image sensor device will have a uniform thickness when etched using the thus obtained etching solution.

Abstract: A method of selectively etching a semiconductor device and manufacturing a BSI image sensor device includes etching a doped silicon substrate with an HNA solution for a predetermined time duration to obtain an etching solution having a concentration C1 of nitrite ions, etching the semiconductor device using the obtained etching solution. Etching the semiconductor device requires an initial concentration C0 of nitride ions that is lower than C1. The HNA solution comprises a hydrofluoric acid (HF), a nitric acid (HNO3), and a acetic acid (CH3COOH). The BSI image sensor device will have a uniform thickness when etched using the thus obtained etching solution.

Abstract: A device includes a first integrated circuit containing a photodiode and a first metal interconnect structure connected to the photodiode, and a second integrated circuit containing a transistor and a second metal interconnect structure connected to the transistor. The first integrated circuit and the second integrated circuit are connected together through the first metal interconnect structure and the second metal interconnect structure. Since no transistor is present around the photodiode, the photodiode has an increased photosensitive area and an improved fill factor, resulting in an increase of the quantum efficiency, higher integration and lower consumption of the image sensor.