Photovoltaic effect

“Photovoltaic effect”, Refers to the phenomenon that light causes a potential difference between different parts of the semiconductor or semiconductor to which the semiconductor is bonded. It is first the process of converting photons (light waves) into electrons and converting light energy into electrical energy; secondly, it is the process of forming voltage. With voltage, it is like building a dam. If the two are connected, a circuit of current will be formed.Steel Profile suppliers

Photovoltaic power generation is a technology that directly converts light energy into electrical energy by utilizing the photovoltaic effect of the semiconductor interface. The key component of this technology is the solar cell. The solar cells are packaged and protected in series to form a large-area solar cell module, and then combined with a power controller and the like to form a photovoltaic power generation device. The advantage of photovoltaic power generation is that it is less restricted by geographical area, because the sun shines on the earth; the photovoltaic system also has the advantages of safe and reliable, no noise, low pollution, no need to consume fuel and erecting transmission lines to generate electricity on site and short construction period. The photovoltaic effect is referred to as the photovoltaic effect, which refers to the phenomenon that light causes a potential difference between a heterogeneous semiconductor or a different portion of a semiconductor and a metal combination.

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Photovoltaic effect refers to the phenomenon that light causes a potential difference between a heterogeneous semiconductor or a different portion where a semiconductor and a metal are combined. It is first the process of converting photons (light waves) into electrons and converting light energy into electrical energy; secondly, it is the process of forming voltage. With voltage, it is like building a dam. If the two are connected, a circuit of current will be formed.

When the P-N junction is illuminated, the intrinsic and extrinsic absorption of the photon by the sample will produce photogenerated carriers (electron-hole pairs). However, only the minority carriers excited by the intrinsic absorption can be caused by the photovoltaic effect. Due to the photogenerated holes generated in the P region, the photogenerated electrons generated in the N region are multi-sub States, and are blocked by the barrier and cannot be over-knotted. Only the photogenerated electrons of the P region and the photogenerated holes of the N region and the electron hole pairs (small children) of the junction region can drift over the junction under the built-in electric field when diffused to the vicinity of the junction electric field. The photogenerated electrons are pulled toward the N region, and the photogenerated holes are pulled toward the P region, that is, the electron hole pairs are separated by the built-in electric field. This results in the accumulation of photogenerated electrons near the boundary of the N region and the accumulation of photogenerated holes near the boundary of the P region. z profile

They produce a photogenerated electric field that is opposite to the direction of the built-in electric field of the thermally balanced P-N junction, with the direction from the P region to the N region. This electric field lowers the barrier, and the amount of decrease is the photo-generated potential difference. The P-terminal is positive and the N-terminal is negative. At this time, the Fermi level is separated, thereby generating a voltage drop, and electrodes are applied on both sides of the silicon wafer and connected to the voltmeter. For crystalline silicon solar cells, the typical value of the open circuit voltage is 0.5 to 0.6V. The more electron-hole pairs that are produced by the illumination at the interface layer, the greater the current. The more light energy absorbed by the interface layer, the larger the cell area of ​​the interface layer, and the greater the current formed in the solar cell.

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