The Results of Our Efforts
Grid Parity is Our Goal
We believe that through durable R & D investment and technology breakthroughs, Gold Stone will become one of the leaders of the photovoltaic industry. Our confidence is rooted in our restless technology innovations.
HDT structure and components mechanism
Firstly, PECVD is used to deposit very thin intrinsic silicon passivation layer and P-type silicon doping layer on the back of N-type mono crystalline silicon wafer after texture formations on silicon surface.
Secondly, very thin intrinsic silicon passivation layer and N-type silicon doped layer are deposited on the front side of the silicon wafer. After the silicon film layer is deposited, transparent oxide conductive film (TCO) and metal lamination are deposited on both sides of the cell using PVD magnetron sputtering coating technology.
Finally, a double-sided metal electrode is prepared on a transparent conductive film by metal grating technology to form a final symmetrical multilayer laminated structure.
High conversion efficiency: HDT solar cells improves the conversion efficiency by 10%-20% compared with traditional crystal silicon cells
Low temperature coefficient: the cell power temperature coefficient is lower than -0.268%/ ºC.At high temperatures, power generation can be increased over 9 %
High stability: anti-PID effect, no LID effect, the attenuation rate of the first year is 50% lower than the traditional crystal silicon cell
Double side power generation: double side power generation; Backside power generation can gain 10%-20%
Breakthrough of equipments and key technology
In recent years, with the deepening technical research and mass production, hetero-junction mass production has made breakthrough progress in key technologies and equipment. For example, On the basis of independent research and development of equipment, GS-SOLAR continuously conducts process optimization.
Stable large-scale production can be achieved with only five process of the whole production line, that is, plasma-enhanced chemical vapor deposition (PECVD), magnetron sputtering (PVD), metal grating formation, and post-treatment cleaning/testing.
Technological innovation leads to product improvement
◎ Low temperature process flow, maximum not exceeding 220 ℃, low energy consumption in the process
◎ Hetero-junction has good compatibility with IBC technology, and the conversion efficiency of the two superposition technologies, HBC is over 26%
◎ Wideband gap induce the high short-circuit current (Isc) and high open voltage (Voc).
◎ The structure of the cell is suitable for the use of ultra-thin silicon as a substrate, which can achieve real flexibility in the future
Functions of Metal Electrode in HDT Solar Cells
The HDT cell structure consists of four silicon films, in which P-type and N-type silicon doped layers are used as the emitter and back electrode fields construct the internal electric field of the cell, and the thickness is about 5nm. The main function of the intrinsic silicon layer on both sides of the mono crystalline silicon wafer is to passivate mono crystalline silicon surface , increase the life of the few particles, and reduce the recombination of the few particles at the interface.
Road Map for Increasing Conversion Efficiency of HDT Solar Cells
1、Reduction of Optical Loss：Reduce the textured surface reflection / Reduce the light absorption by TCO layer and amorphous silicon / Decrease the grid covering area by increasing its aspect ratio
2、Reduction of Surface Recombination Velocity：Improve the cleaning process for textured surface／Optimize the doping concentration of the doped amorphous silicon／Improve the quality of intrinsic layer
3、Reduction of Series Resistance：Increase the conductivity of TCO layer／Reduce the contact resistance between TCO layer and doped amorphous silicon
Mainstream technology of next generation
It is widely believed in the industry that hetero-junction cell technology is the most suitable technology for the future technology to continuously improve and realize economical mass production.
It also shows significant advantages in the power generation capacity and technology scalability of cells per watt, making it a suitable technology platform for the next generation of efficient solar cells.
Photovoltaic industry is growing exponentially and the competition in the industry is heated up. Only the companies who possess strong R&D and innovation competence can become global industry leaders.