CN101714586A - Solar cell with intrinsic isolation structure and manufacturing method thereof - Google Patents

Abstract

The invention relates to a solar cell with an intrinsic isolation structure, which comprises an aluminum back field, a P-type crystal silicon substrate, an intrinsic amorphous silicon film, an N-type amorphous silicon film, a transparent conductive film and a silver grid line in sequence, wherein the P-type crystal silicon substrate is prepared by a metallurgy method. Compared with the prior art, the solar cell has the P-type or N-type crystal silicon substrate made of a silicon material prepared by the low-cost metallurgy method, thereby changing a structure of a traditional cell, overcoming the disadvantages of large countercurrent and low efficiency of the solar cell manufactured from a metallurgical material, and ensuring the large-scale application of the low-cost metallurgical silicon material cell.

Description

A kind of solar cell with intrinsic isolation structure and manufacture method thereof

Technical field

The present invention relates to a kind of solar cell, be meant a kind of solar cell with intrinsic isolation structure and manufacture method thereof especially.

Background technology

Solar energy is the first-selected energy of human social as a kind of widely distributed, inexhaustible, nexhaustible green non-pollution clean energy resource.But because the cost of crystal silicon solar photovoltaic cell is still far above traditional thermoelectricity, the cost of water power at present, therefore, the photovoltaic industry also depends on government subsidy at present, has strong government policy sexual behaviour feature.In order to make solar cell can access large-scale application, reduce battery cost and become the main difficult technical that faces at present.In reducing the cost techniques route of silica-based solar cell, adopting cheaply the high silicon materials of impurity contents such as silicon materials of metallurgy method to substitute traditional fumed materials is a method that effectively reduces cost.The preparation of metallurgy method silicon materials does not have environmental pollution in addition, and production capacity is big, and one-time investment is few.

But, because metallurgy method silicon materials purity does not also reach the level of gas phase material, this has caused adopting conventional batteries technology to exist born deficiency by the crystal silicon solar energy battery of metallurgy method preparation: 1. battery safety in utilization problem: reverse current is big, and this will cause being easy to generate hot spot effect in the assembly that uses this battery.2. efficient is lower: such as polycrystal silicon cell efficient between 13%-15%; And the polycrystal silicon cell of fumed materials is on average 15.5%.

Summary of the invention

Main purpose of the present invention is to overcome hot spot effect and the lower shortcoming of efficient that available technology adopting metallurgy method made solar cell brings, and a kind of solar cell with intrinsic isolation structure and the manufacture method thereof that adopt the metallurgy method made are provided.

The present invention is mainly based on following principle:

Conventional crystal silicon cell generally is to carry out phosphorous diffusion to form N type layer on the crystalline silicon substrate of P type, thereby forms the PN junction structure, and the motion of charge carrier causes in the certain built-in electrical potential difference (internal electric field) of PN junction two ends generation.Under the situation of illumination, the photo-generated carrier of generation hole and electronics under the ordering about of internal electric field flow to P type end and N type end respectively, produce photogenerated current and photoproduction electromotive force.If external load is arranged, the light induced electron of N type end will form current power output by the hole-recombination of external circuits and P type.

At the silicon chip that uses metallurgy method to make, and utilize that said structure and technology makes too can the PN junction in positive electricity pond in, when granting reverse biased, because too much impurity will aggravate tunnel effect and avalanche effect, the electric leakage that impurity brings also can strengthen, and the reverse current of the solar cell of usefulness metallurgy method material, the making of conventional batteries technology is big especially like this.

Mechanism at above reverse current generation, the present invention has added one deck intrinsic silicon in the middle of PN junction, the intrinsic silicon that this layer is pure not only can reduce the tunnel effect and the avalanche effect of barrier region, but also effective isolation the defective leakage current that in the PN junction district, produces by the impurity in the metalluragical silicon.

Based on above principle, the present invention adopts following technical scheme:

A kind of solar cell with intrinsic isolation structure, it comprises aluminium back of the body field/P type crystalline silicon substrate/intrinsic amorphous silicon film/N type amorphous silicon membrane/transparent conductive film/silver grating line successively, wherein P type crystalline silicon substrate is made by metallurgy method.

Aforesaid a kind of solar cell with intrinsic isolation structure, its manufacture method comprises the steps:

Step 1 adopts pecvd process at P type surface of crystalline silicon deposition one deck intrinsic amorphous silicon film and one deck N type amorphous silicon membrane;

Step 2 adopts sputtering technology deposit transparent conductive film on N type amorphous silicon membrane;

Step 3 adopts the method for sputter or evaporation coating to make aluminium back of the body field at the P type crystalline silicon back side;

Step 4 adopts the method for silk screen printing to make Ag electrode and baking on transparent conductive film;

Above-mentioned all is to carry out being lower than under 500 ℃ the temperature in steps.

A kind of solar cell with intrinsic isolation structure, it comprises aluminium back of the body field/N type crystalline silicon substrate/intrinsic amorphous silicon film/P type amorphous silicon membrane/transparent conductive film/silver grating line successively, wherein N type crystalline silicon substrate is made by metallurgy method.

Aforesaid a kind of solar cell with intrinsic isolation structure, its manufacture method comprises the steps:

Step 1 adopts pecvd process at N type surface of crystalline silicon deposition one deck intrinsic amorphous silicon film and one deck P type amorphous silicon membrane;

Step 2 adopts sputtering technology deposit transparent conductive film on P type amorphous silicon membrane;

Step 3 adopts the method for sputter or evaporation coating to make aluminium back of the body field at the N type crystalline silicon back side;

Step 4 adopts the method for silk screen printing to make Ag electrode and baking on transparent conductive film;

Above-mentioned all is to carry out being lower than under 500 ℃ the temperature in steps.

By the above-mentioned description of this invention as can be known, compare with prior art, the present invention has following beneficial effect:

One, the silicon materials that the present invention adopts metallurgy method cheaply to make are made the P type or the N type crystalline silicon substrate of solar cell, changed the structure of conventional batteries, overcome hot spot effect and the lower shortcoming of efficient, made that metallurgy method silicon materials battery is able to large-scale application cheaply by the solar cell of metallurgy method made;

Two, manufacture method of the present invention is all finished below 500 ℃, does not need the processing procedure about 1000 ℃, and less input for heat energy, the damage to silicon chip of also having avoided thermal stress and having caused thus simultaneously;

Three, solar cell of the present invention has very high open circuit voltage, illustrates that solar cell of the present invention has extraordinary junction characteristic.

Description of drawings

Fig. 1 is the structural representation of a kind of solar cell with intrinsic isolation structure of the present invention.

Embodiment

Embodiment one

With reference to Fig. 1, a kind of solar cell with intrinsic isolation structure of the present invention, it comprises aluminium back of the body 1/P type crystalline silicon substrate 2/ intrinsic amorphous silicon film 3/N type amorphous silicon membrane 4/ transparent conductive film 5/ silver grating line 6 successively, wherein P type crystalline silicon substrate is made by metallurgy method, the thickness 100-300 μ m of P type crystalline silicon substrate wherein, resistivity 0.2-3 Ω cm, the thickness of intrinsic amorphous silicon film are 1-20nm, the thickness of N type amorphous silicon membrane is 5-100nm, and the thickness of transparent conductive film is 80-200nm.

A kind of solar cell with intrinsic isolation structure of the present invention comprises the steps: during fabrication

Step 1 adopts P type surface of crystalline silicon deposition one deck intrinsic amorphous silicon film and one deck N type amorphous silicon membrane of pecvd process behind surface-texturing;

Step 2 adopts sputtering technology deposit transparent conductive film on N type amorphous silicon membrane;

Step 3 adopts the method for sputter or evaporation coating to make aluminium back of the body field at the P type crystalline silicon back side;

Step 4 adopts the method for silk screen printing to make Ag electrode and baking on transparent conductive film;

Above-mentioned all is to carry out being lower than under 500 ℃ the temperature in steps.

Confirm that through test the efficient of a kind of solar cell with intrinsic isolation structure of the present invention can reach about 20%.

Wherein, P type crystalline silicon can adopt CZ monocrystalline silicon piece or polysilicon chip.

Embodiment two

A kind of solar cell with intrinsic isolation structure of the present invention, it comprises aluminium back of the body field/N type crystalline silicon substrate/intrinsic amorphous silicon film/P type amorphous silicon membrane/transparent conductive film/silver grating line successively, wherein N type crystalline silicon substrate is made by metallurgy method, the thickness 100-300 μ m of N type crystalline silicon substrate wherein, resistivity 0.2-3 Ω cm, the thickness of intrinsic amorphous silicon film is 1-20nm, and the thickness of P type amorphous silicon membrane is 5-100nm, and the thickness of transparent conductive film is 80-200nm.

A kind of solar cell with intrinsic isolation structure of the present invention comprises the steps: during fabrication

Step 1 adopts N type surface of crystalline silicon deposition one deck intrinsic amorphous silicon film and one deck P type amorphous silicon membrane of pecvd process behind surface-texturing;

Step 2 adopts sputtering technology deposit transparent conductive film on P type amorphous silicon membrane;

Step 3 adopts the method for sputter or evaporation coating to make aluminium back of the body field at the N type crystalline silicon back side;

Step 4 adopts the method for silk screen printing to make Ag electrode and baking on transparent conductive film;

Above-mentioned all is to carry out being lower than under 500 ℃ the temperature in steps.

Confirm that through test the efficient of a kind of solar cell with intrinsic isolation structure of the present invention can reach about 20%.

Wherein, N type crystalline silicon can adopt CZ monocrystalline silicon piece or polysilicon chip.

Above-mentioned only is two embodiments of the present invention, but design concept of the present invention is not limited thereto, and allly utilizes this design that the present invention is carried out the change of unsubstantiality, all should belong to the behavior of invading protection range of the present invention.

Claims (4)

1. solar cell with intrinsic isolation structure is characterized in that: it comprises aluminium back of the body field/P type crystalline silicon substrate/intrinsic amorphous silicon film/N type amorphous silicon membrane/transparent conductive film/silver grating line successively, and wherein P type crystalline silicon substrate is made by metallurgy method.

2. the manufacture method of a kind of solar cell with intrinsic isolation structure as claimed in claim 1 is characterized in that comprising the steps:

Step 1 adopts pecvd process at P type surface of crystalline silicon deposition one deck intrinsic amorphous silicon film and one deck N type amorphous silicon membrane;

Step 2 adopts sputtering technology deposit transparent conductive film on N type amorphous silicon membrane;

Step 3 adopts the method for sputter or evaporation coating to make aluminium back of the body field at the P type crystalline silicon back side;

Step 4 adopts the method for silk screen printing to make Ag electrode and baking on transparent conductive film;

Above-mentioned all is to carry out being lower than under 500 ℃ the temperature in steps.

3. solar cell with intrinsic isolation structure is characterized in that: it comprises aluminium back of the body field/N type crystalline silicon substrate/intrinsic amorphous silicon film/P type amorphous silicon membrane/transparent conductive film/silver grating line successively, and wherein N type crystalline silicon substrate is made by metallurgy method.

4. the manufacture method of a kind of solar cell with intrinsic isolation structure as claimed in claim 3 is characterized in that comprising the steps:

Step 1 adopts pecvd process at N type surface of crystalline silicon deposition one deck intrinsic amorphous silicon film and one deck P type amorphous silicon membrane;

Step 2 adopts sputtering technology deposit transparent conductive film on P type amorphous silicon membrane;

Step 3 adopts the method for sputter or evaporation coating to make aluminium back of the body field at the N type crystalline silicon back side;

Step 4 adopts the method for silk screen printing to make Ag electrode and baking on transparent conductive film;

Above-mentioned all is to carry out being lower than under 500 ℃ the temperature in steps.

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