9results about How to "Increase full well capacity" patented technology

The invention discloses an image sensor PDAF pixel isolation method, a pixel structure and an image sensor, for a PDAF pixel module, the PDAF pixel module comprises a plurality of sub-pixels, first isolation exists between the sub-pixels receiving light of the same phase, second isolation exists between the sub-pixels receiving light of different phases, and the first isolation exists between the sub-pixels receiving light of the same phase and the second isolation exists between the sub-pixels receiving light of different phases. The trench isolation in the first isolation occupies a first proportion, the trench isolation in the second isolation occupies a second proportion, and the second proportion is larger than the first proportion. According to the invention, crosstalk can be effectively suppressed, the loss of the pixel light incoming amount is improved, and the full well capacity is improved, so that the performance of the PDAF is improved, and the working performance of the sensor is improved. Moreover, the first isolation is realized by ion implantation, so that different masks required by different trench isolation offset degrees arranged in the pixel array can be avoided or reduced, and the manufacturing cost of the sensor can be greatly reduced while the performance of the sensor is improved.

The embodiment of the present application discloses an image sensor and an electronic information device for improving full well capacity. The image sensor comprises: a photodiode formed in a semiconductor substrate; the photodiode comprises at least a first doped layer, a second doped layer and a columnar third doped region; the second doped layer wraps the side and bottom of the third doped region; the first doped layer wraps the side and bottom of the second doped layer; the first doped layer and the second doped layer form a first lateral PN junction; the second doped layer and the third doped region form a second lateral PN junction; wherein the first doped layer and the third doped region have the same conductivity type, and the conductivity type is opposite to that of the second doped layer. The embodiment of the present application replaces the central part of the photodiode with a columnar ion doped region (for example, a P-type layer), so that the image sensor with the epitaxial structure can effectively improve the full well capacity, effectively reduce the depletion potential of the center of the photodiode, avoid the occurrence of lag, and reduce the dark current.

This invention provides a pixel structure and its operating method for a radiation-hardened 4T CMOS image sensor. The pixel structure includes a transmission transistor, a reset transistor, a source follower, a row select transistor, an STI bias gate, a photodiode, a floating node, a shallow trench isolation region, and a P-type substrate. The photodiode is surrounded by a P-type substrate, which is enclosed by the shallow trench isolation region. A portion of the shallow trench isolation region is covered by an STI bias gate. The lower right corner of the photodiode is connected to one side of the transmission transistor, and the other side of the transmission transistor is connected to the floating node. The reset transistor, row select transistor, and source follower are sequentially connected after the floating node. The negative bias V of the STIX designed in this invention... STI negative bias V with TX TX The shutdown voltage effectively improves the radiation resistance of the device by suppressing the generation of interface state trap charges at the STI-pixel interface and the generation of dark current in the TX-PD overlap region under the TID effect.

This invention discloses a method for forming a patterned sensor, comprising: providing a substrate; etching the substrate to form trenches in the substrate; and pre-treating the surface of the trenches before forming an epitaxial doped layer in the trenches to change the ion doping concentration gradient distribution in a portion of the substrate at the trench interface, thereby reducing the mutual compensation caused by the diffusion of doped ions near the PN junction interface of the photodiode in subsequent process steps, thereby improving the full-well capacity of the photodiode.

The present invention discloses a pixel circuit for improving the signal-to-noise ratio of a high dynamic range pixel conversion node, comprising a P-type substrate, a large photodiode, a No. 1 transmission gate, a No. 1 charge-voltage conversion node, a No. 2 transmission gate, a No. 2 charge-voltage conversion node, a No. 3 transmission gate, a No. 3 charge-voltage conversion node, a No. 4 transmission gate, and a small photodiode are arranged on the P-type substrate, a No. 4 charge-voltage conversion node is arranged on the left side of the large photodiode, a charge overflow prevention transistor is connected between the No. 4 charge-voltage conversion node and the large photodiode, the No. 4 charge-voltage conversion node is grounded via a No. 2 lateral overflow integrated capacitor, and a transmission gate of overflowed charge is connected between the No. 4 charge-voltage conversion node and the No. 2 charge-voltage conversion node. The present invention significantly improves the signal-to-noise ratio when the SP1L signal is switched to the SP2H signal while ensuring that the full well capacity of the high dynamic range pixel does not change significantly, and significantly optimizes the imaging quality of the high dynamic pixel.

The invention relates to a large full-well TDI-CMOS pixel structure, belonging to the field of CMOS image sensors; the structure comprises 6 CCD electrodes, 4 column isolations and 3 CCD channels; wherein the 4 column isolations and the 3 CCD channels are all rectangular parallelepiped structures; the 4 column isolations and the 3 CCD channels are arranged adjacently and staggered to form a rectangular parallelepiped base; the 6 CCD electrodes are evenly arranged at equal intervals on the upper surface of the rectangular parallelepiped base, and the axial direction of the CCD electrodes is perpendicular to the axial direction of the column isolations and the CCD channels; the invention is suitable for a CCD-CMOS fusion type TDI image sensor, and in particular can increase the full-well capacity performance without affecting the voltage swing, the charge transfer efficiency and the anti-dispersion capability.

The invention provides an image sensor and a manufacturing method thereof, and the method comprises the steps: carrying out the non-crystallization ion implantation of a central region of a photodiode region through an implantation window of a patterned mask layer, forming a non-crystallization region in a substrate of the central region, and enlarging the implantation window of the patterned mask layer, the expanded injection window is enabled to expose the edge area of the photodiode area, and then second conductive type ions are injected into one of the central area and the edge area of the photodiode area through the expanded injection window to form a photodiode buried layer. Since the central region of the photodiode region is amorphized and the edge region is not amorphized, when the central region and the edge region are simultaneously subjected to second conduction type ion implantation, the edge region is easier to generate ion diffusion than the central region, and when the potential gradient of the central region reaches the level of the prior art, the edge region is easier to generate ion diffusion. The potential of the marginal region is relatively increased from low, and the potential gradient of the marginal region is effectively improved, so that the photoelectron storage capability of the photodiode is improved, and the effect of improving the full well capacity is achieved.

The invention discloses a pixel structure and a forming method thereof, and the method comprises the steps: providing a substrate which is provided with a first surface and a second surface which are opposite to each other, and comprises a first region and a second region, and the first region and the second region are arranged from the first surface to the second surface in a direction perpendicular to the surface of the substrate; forming a photoelectric doped region in the second region, wherein the photoelectric doped region has a first projection on the surface of the substrate; a diffusion region is formed in the first region, the diffusion region has a second projection on the surface of the substrate, and the second projection is within the range of the first projection; and forming a plurality of gate structures in the first region, wherein each gate structure penetrates through the diffusion region along the direction vertical to the substrate. The second projection is within the range of the first projection, and the diffusion region and the photoelectric doping region are arranged in an overlapped manner in the direction perpendicular to the surface of the substrate, so that the transmission path of electrons flowing from the photoelectric doping region to the diffusion region is shortened, the electron transmission rate is improved, the pixel full well capacity of unit area is improved, and the dynamic range of the pixel structure is improved.

The application provides an image sensor forming method and an image sensor. The forming process of the image sensor comprises at least two bonding processes of a semiconductor substrate wafer; wherein, a lateral PN junction and a pinning layer are formed in the semiconductor substrate wafer before the first bonding, and a logic circuit region is formed after the first bonding and before the second bonding. The technology in the application has high feasibility because of simple process, high full-well capacity and completion through a self-alignment process, and is not limited by temperature.