CN210805782U

CN210805782U - N-type local high-low junction back surface field double-sided solar cell

Info

Publication number: CN210805782U
Application number: CN201921960928.9U
Authority: CN
Inventors: 王璞; 吴俊旻; 谢毅; 张鹏; 王岚
Original assignee: Tongwei Solar Meishan Co Ltd
Current assignee: Tongwei Solar Meishan Co Ltd
Priority date: 2019-11-14
Filing date: 2019-11-14
Publication date: 2020-06-19
Anticipated expiration: 2029-11-14

Abstract

The utility model discloses a two-sided solar cell of local high low knot back of body surface field of n type relates to solar cell technical field, the utility model discloses an n type silicon substrate, n type silicon substrate bottom from the top down is provided with silicon oxide passivation layer, intrinsic amorphous silicon layer and back silicon nitride antireflection layer, and n type silicon substrate bottom inlays and is equipped with a plurality of phosphorus sources doping layer, and phosphorus sources doping layer bottom is connected with the back metal electrode layer that runs through silicon oxide passivation layer, intrinsic amorphous silicon layer and back silicon nitride antireflection layer simultaneously, the utility model provides a high two-sided solar cell's of n type back battery open circuit voltage reduces series resistance and improves the fill factor, under the condition that does not reduce positive efficiency, improves the two-sided rate of battery.

Description

N-type local high-low junction back surface field double-sided solar cell

Technical Field

The utility model relates to a solar cell technical field, more specifically relate to a two-sided solar cell of n type local height knot back of body surface field.

Background

In recent years, the rapid development of renewable energy sources is increasing day by day, and the more popular renewable energy source fields are solar energy, wind energy, tidal energy and the like. Compared with the traditional energy, the solar energy has the characteristics of simple utilization, safety, no pollution and the like, and becomes the focus of research in the field of renewable new energy. The basic principle of solar cell power generation is photovoltaic effect, the solar cell is a new energy device for converting sunlight into electric energy, with the increasing application fields of solar power generation, the preferential problems of new policies and the like, the requirement of photovoltaic power generation cost is greatly reduced, the cost of photovoltaic power generation is greatly reduced, and the requirement of efficiency improvement and cost reduction in the field of battery manufacturing is reduced. The traditional single-sided power generation battery has the problems of low conversion efficiency and low power generation capacity, so that researchers engaged in solar battery research are required to research the double-sided solar battery, silicon substrate materials are saved, and the power generation capacity is increased. The double-sided solar cell can be applied to lakes to form fishing light complementation, can also be applied to expressways, photovoltaic building integration, snow fields and the like, and the back of the solar cell fully utilizes diffuse reflection light to increase the generating capacity of the double-sided solar cell.

Aiming at the existing double-sided solar cell with an n-type silicon substrate, the lower surface of the double-sided solar cell is provided with a laminated film of aluminum oxide and silicon nitride, and the filling factor and the open-circuit voltage of the back side cell of the double-sided solar cell are lower, so that the back side cell of the double-sided solar cell is low in efficiency and the double-sided rate is lower.

Therefore, it is a realistic meaning for those skilled in the art how to solve the above technical problems.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a: in order to solve the fill factor and the open circuit voltage ratio of the two-sided solar cell of current n type silicon substrate and lower, lead to two-sided solar cell back battery inefficiency, the technical problem that two-sided rate is also lower, the utility model provides a two-sided solar cell of local high low junction back surface field of n type.

The utility model discloses a realize above-mentioned purpose and specifically adopt following technical scheme:

the utility model provides a two-sided solar cell of local high low knot back surface field of n type, includes n type silicon substrate, and n type silicon substrate bottom from the top down is provided with silicon oxide passivation layer, intrinsic amorphous silicon layer and back silicon nitride antireflection layer, and n type silicon substrate bottom inlays and is equipped with a plurality of phosphorus source doping layers, and phosphorus source doping layer bottom is connected with the back metal electrode layer that runs through silicon oxide passivation layer, intrinsic amorphous silicon layer and back silicon nitride antireflection layer simultaneously.

Furthermore, a boron source doping layer and a front silicon nitride antireflection layer are sequentially arranged on the top of the n-type silicon substrate from bottom to top, a plurality of front metal electrode layers in one-to-one correspondence with the positions of the phosphorus source doping layers are arranged on the upper surface of the boron source doping layer, and the front metal electrode layers penetrate through the front silicon nitride antireflection layer.

Furthermore, the front metal electrode layer and the back metal electrode layer are both made of Ag or Ag alloy or Cu and at least one of Mo, W, Ti, Ni, Al, Mg, Ta and Sn.

Furthermore, the thickness of the n-type silicon substrate is 100-160 mu m, the thickness of the boron source doping layer is 300-500nm, the thickness of the front silicon nitride antireflection layer is 80-100nm, the thickness of the silicon oxide passivation layer is 1-10nm, the thickness of the intrinsic amorphous silicon layer is 2-10nm, the thickness of the back silicon nitride antireflection layer is 100-150nm, and the thickness of the phosphorus source doping layer is 300-500 nm.

Furthermore, the width of the electrode grid lines of the back metal electrode layer and the front metal electrode layer is 40-80um, and the height of the electrode grid lines is 25-50 um.

The utility model has the advantages as follows:

1. the bottom of the n-type silicon substrate is embedded with the phosphorus source doping layers, so that a back surface field high-low junction structure is formed, the open-circuit voltage of the back surface battery of the double-sided solar battery is improved, the back surface metal electrode layer and the phosphorus source doping layers form ohmic contact, the series resistance of the battery is reduced, the photoelectric conversion efficiency and the double-sided rate of the back surface battery of the double-sided solar battery are improved under the condition that the front surface efficiency is not reduced, the generated energy of a battery cell assembly is increased, the occupied area of a power station is reduced, the limited space resources are fully utilized, and the silicon substrate material is saved. The test shows that the utility model has the front efficiency of more than 22.38 percent, the double-face rate of more than 78.4 percent and the generated energy gain of 5 to 15 percent.

Drawings

Fig. 1 is a schematic structural diagram of an n-type local high-low junction back surface field bifacial solar cell of the present invention;

fig. 2 is a schematic structural diagram of an n-type local high-low junction back surface field single-sided solar cell in example 2.

Reference numerals: 1-a front metal electrode layer, 2-a front silicon nitride antireflection layer, 3-a boron source doped layer, a 4-n type silicon substrate, 5-a phosphorus source doped layer, 6-a silicon oxide passivation layer, 7-an intrinsic amorphous silicon layer, 8-a back silicon nitride antireflection layer, 9-a back metal electrode layer and 10-an aluminum back field layer.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the invention.

In the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be construed as limiting the present application.

The features and properties of the present invention are described in further detail below with reference to examples.

Example 1

As shown in fig. 1, the present embodiment provides an n-type local high-low junction back surface field double-sided solar cell, which includes an n-type silicon substrate 4, a silicon oxide passivation layer 6, an intrinsic amorphous silicon layer 7 and a back silicon nitride antireflection layer 8 are disposed at the bottom of the n-type silicon substrate 4 from top to bottom, a plurality of phosphorus source doping layers 5 are embedded at the bottom of the n-type silicon substrate 4, and a back metal electrode layer 9 penetrating through the silicon oxide passivation layer 6, the intrinsic amorphous silicon layer 7 and the back silicon nitride antireflection layer 8 simultaneously is connected to the bottom of the phosphorus source doping layer 5.

The bottom of the n-type silicon substrate 4 is embedded with the phosphorus source doping layers 5, so that a back surface field high-low junction structure is formed, the open-circuit voltage of the back surface battery of the double-sided solar battery is improved, the back surface metal electrode layer 9 and the phosphorus source doping layers 5 form ohmic contact, the series resistance of the battery is reduced, the photoelectric conversion efficiency and the double-sided rate of the back surface battery of the double-sided solar battery are improved under the condition that the front surface efficiency is not reduced, the generated energy of a battery cell assembly is increased, the occupied area of a power station is reduced, the limited space resources are fully utilized, and the silicon substrate material is saved. The test shows that the battery prepared by the utility model has the positive efficiency of more than 22.38 percent, the double-sided rate of more than 78.4 percent and the generated energy gain of 5 to 15 percent.

As a preferred technical solution of this embodiment:

the top of the n-type silicon substrate 4 is sequentially provided with a boron source doping layer 3 and a front silicon nitride antireflection layer 2 from bottom to top, the upper surface of the boron source doping layer 3 is provided with a plurality of front metal electrode layers 1 which are in one-to-one correspondence with the positions of the phosphorus source doping layer 5, and the front metal electrode layers 1 all penetrate through the front silicon nitride antireflection layer 2.

As a preferred technical solution of this embodiment:

the front metal electrode layer 1 and the back metal electrode layer 9 are both made of Ag or Ag alloy or Cu and at least one of Mo, W, Ti, Ni, Al, Mg, Ta and Sn, and both meet the use requirements.

As a preferred technical solution of this embodiment:

the thickness of the n-type silicon substrate 4 is 100-160 mu m, the thickness of the boron source doping layer 3 is 300-500nm, the thickness of the front silicon nitride antireflection layer 2 is 80-100nm, the thickness of the silicon oxide passivation layer 6 is 1-10nm, the thickness of the intrinsic amorphous silicon layer 7 is 2-10nm, the thickness of the back silicon nitride antireflection layer 8 is 100-150nm, the thickness of the phosphorus source doping layer 5 is 300-500nm, the electrode grid line widths of the back metal electrode layer 9 and the front metal electrode layer 1 are both 40-80 mu m, the heights of the electrode grid lines are both 25-50 mu m, the thicknesses of all layers are optimized, and the performance of the battery is improved.

The utility model discloses the principle also can be applied to single face solar cell, as follows embodiment 2:

example 2

As shown in fig. 2, this embodiment provides an n-type local high-low junction back surface field single-sided solar cell, which includes an n-type silicon substrate 4, a silicon oxide passivation layer 6 and a back silicon nitride antireflection layer 8 are disposed at the bottom of the n-type silicon substrate 4 from top to bottom, a plurality of phosphorus source doping layers 5 are embedded at the bottom of the n-type silicon substrate 4, an aluminum back surface field layer 10 penetrating through the silicon oxide passivation layer 6 and the back silicon nitride antireflection layer 8 simultaneously is connected to the bottom of the phosphorus source doping layer 5, the aluminum back surface field layer 10 extends to cover the lower surface of the back silicon nitride antireflection layer 8, a boron source doping layer 3 and a front silicon nitride antireflection layer 2 are sequentially disposed at the top of the n-type silicon substrate 4 from bottom to top, a plurality of front metal electrode layers 1 corresponding to the positions of the phosphorus source doping layers 5 one by one are disposed on the upper surface of the boron source doping layer 3, and the front metal electrode.

The above description is only for the preferred embodiment of the present invention, and the present invention is not limited thereto, the protection scope of the present invention is defined by the claims, and all structural changes equivalent to the contents of the description and drawings of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a two-sided solar cell of local high low junction back surface field of n type, including n type silicon substrate (4), n type silicon substrate (4) bottom from the top down is provided with silicon oxide passivation layer (6), intrinsic amorphous silicon layer (7) and back silicon nitride antireflection layer (8), its characterized in that, n type silicon substrate (4) bottom inlays and is equipped with a plurality of phosphorus source doping layer (5), phosphorus source doping layer (5) bottom is connected with back metal electrode layer (9) that run through silicon oxide passivation layer (6), intrinsic amorphous silicon layer (7) and back silicon nitride antireflection layer (8) simultaneously.

2. The n-type local high-low junction back surface field double-sided solar cell as claimed in claim 1, wherein a boron source doping layer (3) and a front silicon nitride antireflection layer (2) are sequentially arranged on the top of the n-type silicon substrate (4) from bottom to top, a plurality of front metal electrode layers (1) corresponding to the phosphorus source doping layer (5) in position one by one are arranged on the upper surface of the boron source doping layer (3), and the front metal electrode layers (1) all penetrate through the front silicon nitride antireflection layer (2).

3. The n-type local high-low junction back surface field bifacial solar cell of claim 2, wherein the front metal electrode layer (1) and the back metal electrode layer (9) are both Ag or an Ag alloy or Cu or an alloy of Cu and at least one of Mo, W, Ti, Ni, Al, Mg, Ta and Sn.

4. The n-type local high-low junction back surface field double-sided solar cell as claimed in claim 2, wherein the thickness of the n-type silicon substrate (4) is 100-160 μm, the thickness of the boron source doping layer (3) is 300-500nm, the thickness of the front silicon nitride anti-reflection layer (2) is 80-100nm, the thickness of the silicon oxide passivation layer (6) is 1-10nm, the thickness of the intrinsic amorphous silicon layer (7) is 2-10nm, the thickness of the back silicon nitride anti-reflection layer (8) is 100-150nm, and the thickness of the phosphorus source doping layer (5) is 300-500 nm.

5. The n-type local high-low junction back surface field double-sided solar cell as claimed in any one of claims 2 to 4, wherein the electrode grid line width of the back metal electrode layer (9) and the electrode grid line width of the front metal electrode layer (1) are both 40-80um, and the height thereof is both 25-50 um.