CN104377268A - Solar cell panel and crystal silicon wafer thereof - Google Patents

Abstract

The invention relates to the technical field of solar energy, in particular to a solar energy battery panel and a crystalline silicon wafer thereof. The solar battery panel is composed of the following parts: a glass substrate with an evaporation layer laminated on one side, a transparent electrode layer on the lower layer of the evaporation layer, a transparent The lower layer of the photoelectrode layer has a crystalline silicon wafer, and the lower layer of the crystalline silicon wafer has a back electrode layer. Compared with the prior art where the back surface of the crystalline silicon wafer is only provided with an all-aluminum back field, the transmittance of sunlight is significantly reduced, and the photoelectric conversion efficiency of the crystalline silicon wafer is greatly improved. In addition, the local aluminum back field formed by etching the contact window and setting the aluminum film on the contact window, compared with the full aluminum back field, because the high recombination area of the aluminum back field is reduced, its effect on the back surface of the crystalline silicon wafer The impact of the minority carrier lifetime is also reduced accordingly, further improving the photoelectric conversion efficiency of the crystalline silicon wafer.

Description

A kind of solar battery panel and its crystalline silicon chip

technical field

The invention relates to the technical field of solar energy, in particular to a solar energy battery panel and a crystalline silicon wafer thereof.

Background technique

With the increasing shortage of energy, the development of renewable energy has attracted more and more attention, and the research on solar cells has continued to deepen. The focus of the development of crystalline silicon solar cells is high efficiency and low cost. Solar energy is an inexhaustible renewable energy source for human beings. It is also clean energy and does not produce any environmental pollution. Among the effective utilization of solar energy; solar photovoltaic utilization is the fastest-growing and most dynamic research field in recent years, and it is one of the most eye-catching projects. To this end, people have researched and developed solar cells. The production of solar cells is mainly based on semiconductor materials. Its working principle is to use photoelectric materials to absorb light energy and then undergo photoelectric conversion reactions.

The crystalline silicon wafer of a conventional solar panel adopts an all-aluminum back field structure printed on the back. The specific production process is: the crystalline silicon wafer undergoes texturing, diffusion, and PSG removal, and contains a silicon oxide layer with a relatively high phosphorus concentration, which is called phosphorus. Silicon glass) and an anti-reflection film (a film coated on the light-receiving surface of a crystalline silicon wafer to reduce sunlight reflection) are formed on the front, and an aluminum layer is placed on the back surface to increase the open-circuit voltage and short-circuit current, that is, the all-aluminum back field. Although the structure set by this process has many advantages, the back surface of the aluminum-silicon alloy formed by sintering has certain advantages in reducing recombination (recombination: a way to reduce the minority carriers on the back of the crystal silicon wafer) and back reflection. The limitations of the aluminum-silicon alloy region itself, which is the high recombination region, are more obvious, and the reflectivity of the aluminum back field to sunlight is low, and the long-wave response is poor, which limits the further improvement of the photoelectric conversion efficiency of solar cells.

Contents of the invention

To solve the above problems, the present invention provides a solar cell panel and a crystalline silicon wafer thereof.

The technical solution adopted by the present invention is: solar cell panels are manufactured in the form of a plurality of solar cell units electrically connected and integrated on one plate. For this reason, a glass substrate as a transparent insulating layer is first provided, and TCO and other materials to vapor-deposit transparent electrode layers. In order to evaporate the transparent electrode layer, various physical and chemical evaporation methods such as plasma evaporation, vacuum evaporation, and sputtering can be used. Afterwards, patterning is carried out on the transparent electrode layer by using a laser scribing machine, and it is separated into a plurality of elongated strip-shaped transparent electrodes, and then a crystalline silicon wafer covering the transparent electrode layer is vapor-deposited with a-Si and other materials. The scribing machine performs patterning and divides into a plurality of crystalline silicon wafers. At this time, the dividing grooves between the crystalline silicon wafers are extended in the same direction as the separating grooves between the transparent electrode layers, and then vapor-deposited with metal materials such as aluminum The back electrode layer covering the crystalline silicon wafer is patterned with a laser scribing machine and separated into multiple back electrodes. In the solar cell panel manufactured through the above-mentioned process, the strip-shaped transparent electrodes and the crystalline silicon wafer are stacked on top of each other. And the back electrode becomes a unit, which is integrated by multiple solar cells as a whole. Since the back electrode layer is vapor-deposited so as to fill the dividing grooves between the crystalline silicon wafers, the transparent electrode of any solar cell is connected to the back electrode of another cell adjacent to the cell. That is, the dividing grooves between the crystalline silicon wafers are also used as the grooves for connecting cells, so all the solar cells on the substrate are electrically connected in series. External electrodes are connected to both ends of a plurality of solar cells connected in series.

The beneficial effect of the present invention is that the dangling bonds on the back surface of the crystalline silicon wafer are passivated through the passivation structure composed of the above three-layer film, which improves the sunlight utilization rate of the crystalline silicon wafer, and adopts the arrangement mode of the three-layer film , so that the passivation structure is along the direction from close to the back surface of the crystalline silicon wafer to far away from the back surface of the crystalline silicon wafer, the refractive index is from low to high, and the film thickness is from high to low, thereby forming multiple reflections on sunlight, which improves the maximum The reflectivity of the back surface of the crystalline silicon wafer enhances its reabsorption of sunlight. Compared with the prior art where the back surface of the crystalline silicon wafer is only provided with an all-aluminum back field, the transmittance of sunlight is significantly reduced, greatly improving the performance of the crystalline silicon wafer. photoelectric conversion efficiency. In addition, the local aluminum back field formed by etching the contact window and setting the aluminum film on the contact window, compared with the full aluminum back field, because the high recombination area of the aluminum back field is reduced, its effect on the back surface of the crystalline silicon wafer The impact of the minority carrier lifetime is also reduced accordingly, further improving the photoelectric conversion efficiency of the crystalline silicon wafer.

Detailed ways

A solar cell panel is manufactured in the form of a plurality of solar cell units electrically connected and integrated on one plate. For this purpose, a glass substrate as a transparent insulating layer is firstly provided, and a transparent electrode layer is evaporated on the glass substrate with TCO and other materials. In order to evaporate the transparent electrode layer, various physical and chemical evaporation methods such as plasma evaporation, vacuum evaporation, and sputtering can be used. Afterwards, patterning is carried out on the transparent electrode layer by using a laser scribing machine, and it is separated into a plurality of elongated strip-shaped transparent electrodes, and then a crystalline silicon wafer covering the transparent electrode layer is vapor-deposited with a-Si and other materials. The scribing machine performs patterning and divides into a plurality of crystalline silicon wafers. At this time, the dividing grooves between the crystalline silicon wafers are extended in the same direction as the separating grooves between the transparent electrode layers, and then vapor-deposited with metal materials such as aluminum The back electrode layer covering the crystalline silicon wafer is patterned with a laser scribing machine and separated into multiple back electrodes. In the solar cell panel manufactured through the above-mentioned process, the strip-shaped transparent electrodes and the crystalline silicon wafer are stacked on top of each other. And the back electrode becomes a unit, which is integrated by multiple solar cells as a whole. Since the back electrode layer is vapor-deposited so as to fill the dividing grooves between the crystalline silicon wafers, the transparent electrode of any solar cell is connected to the back electrode of another cell adjacent to the cell. That is, the dividing grooves between the crystalline silicon wafers are also used as the grooves for connecting cells, so all the solar cells on the substrate are electrically connected in series. External electrodes are connected to both ends of a plurality of solar cells connected in series.

Claims (2)

1. solar panel and a crystal silicon chip thereof, is characterized in that: described solar panel forms by with lower part: superimposed layer has the glass substrate of evaporation layer, there is transparent electrode layer in the lower floor of evaporation layer, there is crystal silicon chip in the lower floor of euphotic electrode layer, there is back electrode layer in the lower floor of crystal silicon chip; The back side of described crystal silicon chip is provided with ground floor SiO2 film, second layer TiO2 film, third layer SiO2 film.

2. a manufacture method for solar panel,

A, choose glass substrate as transparent insulating layer, adopt vacuum deposition method evaporation transparent electrode layer with TCO on the glass substrate;

B, first take the assigned position of substrate, obtain image data, by comparing the reference data of image data and regulation, calculate position error, according to position error, rotate substrate to predetermined angular, the glass substrate one side at transparent insulating layer being laminated with evaporation layer is loaded on brace table fixing;

C, irradiate the laser that can pass through transparent insulating layer to described substrate, utilize laser to portray machine composition on transparent electrode layer, be separated into the transparency electrode of multiple elongated, belt-shaped;

The crystal silicon chip of d, use a-Si evaporation covering transparent electrode layer, utilizes laser scribing machine carry out composition and be divided into multiple crystal silicon chip;

E, cover the back electrode layer of crystal silicon chip with aluminium-vapour deposition, utilize laser scribing machine carry out composition and be separated into multiple backplate.