Method of generating pixel array layout for image sensor and layout generating system using the method
A method of generating a pixel array layout for an image sensor (wherein the image sensor includes a plurality of unit pixels, and each of the plurality of unit pixels includes a plurality of transistors) includes forming each unit pixel to include a shallow trench isolation (STI). The STI is between a deep trench isolation (DTI) area and one of a p-well region and source and drain regions of each transistor. The p-well region is below a gate of each of the transistors, and the DTI area is filled with at least two materials.
1. A pixel array generating system, comprising:
a layout file storage medium configured to store a plurality of layouts for a pixel array of an image sensor;
a layout generator configured to select a layout from among the plurality of layouts and generate a final layout by one of reading the selected layout from the layout file storage medium and generating a new layout based on the selected layout; and
a semiconductor processing apparatus configured to manufacture the pixel array of the image sensor based on the generated final layout,
wherein the plurality of layouts includes a layout of a first unit pixel that includes a layout of a plurality of first transistors and a shallow trench isolation (STI), the STI being formed between a first p-well region and a first deep trench isolation (DTI) area, the first p-well region being below a gate of a first drive transistor from among the plurality of first transistors,
wherein the plurality of layouts includes a layout of a second unit pixel that includes a layout of a plurality of second transistors and a second DTI area, the second DTI area being formed adjacent to a second p-well region, the second p-well region being below a gate of a second drive transistor from among the plurality of second transistors, and
wherein the layout generator is further configured to generate one of the layout of the first unit pixel and the layout of the second unit pixel as the final layout based on desired performance characteristics of the image sensor.
2. The pixel array generating system of claim 1 , wherein the first unit pixel further comprises a floating diffusion region in contact with the STI.
3. The pixel array generating system of claim 2 , wherein the STI is formed between the floating diffusion and the plurality of first transistors.
4. The pixel array generating system of claim 1 , wherein the layout of the first unit pixel comprises a plurality of first unit pixels arranged in a matrix form.
5. The pixel array generating system of claim 1 , wherein the STI is formed between a third p-well region and the first DTI area, the third p-well region being below a gate of a select transistor from among the plurality of first transistors.
6. The pixel array generating system of claim 1 , wherein the first unit pixel further comprises a ground formed adjacent to a gate of a transfer transistor from among the plurality of first transistors.
7. The pixel array generating system of claim 1 , wherein the first DTI area is filled with at least two materials.
8. The pixel array generating system of claim 1 , wherein each of the first DTI area and the second DTI area are filled with at least two materials.
9. The pixel array generating system of claim 1 , wherein
the layout generator is further configured to generate the layout of the first unit pixel as the final layout if a desired signal-to-noise ratio (SNR) of the image sensor is greater than or equal to a threshold SNR; and
the layout generator is further configured to generate the layout of the second unit pixel as the final layout if the desired SNR of the image sensor is less than the threshold SNR.