Phosphorus diffusion method for crystalline silicon solar cells

A technology for solar cells and phosphorus diffusion, applied in the field of solar cells, can solve the problems of inconsistent PN junction, large temperature fluctuations, large differences, etc., and achieve the effects of improving inter-chip uniformity, reducing recombination centers, and low cost

CN105780127BActive Publication Date: 2018-08-07YANCHENG CANADIAN SOLAR INC
16 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Publication Date
2018-08-07

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
Patent Text Reader

Abstract

The invention discloses a phosphorus diffusion method of a crystalline silicon solar cell. The phosphorus diffusion method comprises the following steps: (1) heating a diffusion furnace to 760-780 DEG C, and feeding; (2) adjusting the temperature to 780-790 DEG C; (3) introducing a phosphorus source carrying gas and dry oxygen for low-temperature diffusion; (4) stopping introducing the phosphorus source carrying gas and the dry oxygen, increasing the temperature inside the furnace to 820-840 DEG C, and boosting; (5) performing constant-temperature boosting; (6) reducing the temperature inside the diffusion furnace to 700-750 DEG C, and performing cooling diffusion; and (7) cooling, and discharging. As annealing steps and steps of two times of diffusion are combined, the problem that in the prior art the surface doping solubility caused by annealing is reduced secondarily and impurities are widely distributed can be solved, the impurity distribution meets the shallow junction and narrow impurity requirements, moreover the yield is increased, and the photoelectric conversion efficiency can be improved.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to a phosphorus diffusion method for a crystalline silicon solar cell, which belongs to a diffusion junction process for manufacturing a solar cell and belongs to the technical field of solar cells. Background technique

[0002] Conventional fossil fuels are increasingly depleted. Among all sustainable energy sources, solar energy is undoubtedly the cleanest, most common and most potential alternative energy source. At present, among all solar cells, crystalline silicon solar cells are one of the solar cells that have been widely commercialized. This is due to the extremely abundant reserves of silicon materials in the earth's crust. Cells have excellent electrical and mechanical properties, therefore, crystalline silicon solar cells occupy an important position in the field of photovoltaics.

[0003] The manufacturing process of crystalline silicon solar cells widely used at present has also been standardized. The main steps are...

Examples

Embodiment 1

[0035] A phosphorus diffusion method for a crystalline silicon solar cell, comprising the steps of:

[0036] (1) Raise the temperature of the diffusion furnace to 780°C, and the maximum nitrogen flow rate is 20,000 sccm; enter the boat, and the time of entering the boat is controlled at 600-800 seconds;

[0037] (2) The temperature is raised to 790° C., the maximum nitrogen flow is 20000 sccm, and the pressure in the furnace is controlled at 100 mba; the temperature adjustment time is controlled at 600 to 800 seconds;

[0038] (3) Keep the above temperature, pressure and large nitrogen flow rate constant, and at the same time introduce phosphorus-carrying source gas and dry oxygen to carry out low-temperature diffusion, and the diffusion time is 600 to 900 seconds;

[0039] The flow rate of the oxygen is 1500 sccm;

[0040] The flow rate of the phosphorus source gas is 1L / min;

[0041] (4) Stop feeding the phosphorus-carrying source gas and dry oxygen, raise the temperature ...