In this paper, performance of PECVD SiO 2 /Si 3 N 4 double layers electrets with different thicknesses were investigated detailedly in respect of chargeability, storage charge stability in high temperature and reliabi...In this paper, performance of PECVD SiO 2 /Si 3 N 4 double layers electrets with different thicknesses were investigated detailedly in respect of chargeability, storage charge stability in high temperature and reliability in high humidity environment. Samples with different thicknesses of Si 3 N 4 and SiO 2 were prepared on Pyrex 7740 glass substrates and characterized by isothermal and high humidity charge decay. The results of experiment approved that the PECVD SiO 2 /Si 3 N 4 double layers electrets on glass substrate has as good chargeability and charge stability in high temperature and high humidity environment as thermal oxidation or APCVD/LPCVD ones on silicon substrates. The experiment results indicated that a Si 3 N 4 layer no less than 50 nm is necessary for good charge stability in high temperature and a Si 3 N 4 layer thicker than 500 nm decreases the chargeability. Even a 2 nm Si 3 N 4 layer is enough to significantly improve the charge stability in high humidity environment. Thick SiO 2 layer can increase the surface potential of electrets under the same charging condition and its charge stability in high temperature. However, the electrets with high surface potential also exhibit poor uniformity of charge stability in high humidity environment.展开更多
In boron-doped p+-n crystalline silicon（Si） solar cells, p-type boron doping control and surface passivation play a vital role in the realization of high-efficiency and low cost pursuit. In this study, boron-doped p...In boron-doped p+-n crystalline silicon（Si） solar cells, p-type boron doping control and surface passivation play a vital role in the realization of high-efficiency and low cost pursuit. In this study, boron-doped p+-emitters are formed by boron diffusion in an open-tube furnace using borontribromide（BBr3） as precursor. The formed emitters are characterized in detail in terms of shape of the doping profile, surface doping concentration, junction depth, sheet resistance and removal of the boron-rich layer（BRL）. In the aspect of BRL removal, three different methods were adopted to investigate their influence on device performance. The results demonstrate that our proposed chemical etch treatment（CET） with the proper etching time could be an effective way to remove the BRL.After removal of the BRL, Al;O;/SiN;stacks are deposited by atomic layer deposition（ALD） and plasma-enhanced chemical vapor deposition（PECVD） to passivate the cell surface. It was found that a reasonably-high implied Voc of 680 mV has been achieved for the fabricated n-type Si solar cells.展开更多
A successful experimental synthesis of pure crystalline β-and α-C3N4 films on Si( 100) substrate was carried out by bias-assisted hot filament chemical vapor deposition (bias-HFCVD). It is found that a mixed-phase C...A successful experimental synthesis of pure crystalline β-and α-C3N4 films on Si( 100) substrate was carried out by bias-assisted hot filament chemical vapor deposition (bias-HFCVD). It is found that a mixed-phase C3-x-Six-Ny buffer layer was formed between the Si substrate and the C-N film. A "lattice match selection" was proposed to study the growth mechanism of C3N4 clusters composed of many crystal columns with hexagonal facets.展开更多
基金supported by the National Basic Research Program of China ("973" Program) (Grant No. 2009CB320300)
文摘In this paper, performance of PECVD SiO 2 /Si 3 N 4 double layers electrets with different thicknesses were investigated detailedly in respect of chargeability, storage charge stability in high temperature and reliability in high humidity environment. Samples with different thicknesses of Si 3 N 4 and SiO 2 were prepared on Pyrex 7740 glass substrates and characterized by isothermal and high humidity charge decay. The results of experiment approved that the PECVD SiO 2 /Si 3 N 4 double layers electrets on glass substrate has as good chargeability and charge stability in high temperature and high humidity environment as thermal oxidation or APCVD/LPCVD ones on silicon substrates. The experiment results indicated that a Si 3 N 4 layer no less than 50 nm is necessary for good charge stability in high temperature and a Si 3 N 4 layer thicker than 500 nm decreases the chargeability. Even a 2 nm Si 3 N 4 layer is enough to significantly improve the charge stability in high humidity environment. Thick SiO 2 layer can increase the surface potential of electrets under the same charging condition and its charge stability in high temperature. However, the electrets with high surface potential also exhibit poor uniformity of charge stability in high humidity environment.
基金Project supported by the Beijing Municipal Science and Technology Commission,China(No.Z151100003515003)the Beijing Natural Science Foundation(No.4173077,2184112)+3 种基金the Fundamental Research Funds for the Central Universities,China(Nos.FRF-BR-16-018A,FRF-TP-17-022A1,06400071)the National Natural Science Foundation of China(Nos.110751402347,61274134,51402064,61274059,51602340)the Beijing Municipal Innovation and Research Base,China(No.Z161100005016095)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2015387)
文摘In boron-doped p+-n crystalline silicon（Si） solar cells, p-type boron doping control and surface passivation play a vital role in the realization of high-efficiency and low cost pursuit. In this study, boron-doped p+-emitters are formed by boron diffusion in an open-tube furnace using borontribromide（BBr3） as precursor. The formed emitters are characterized in detail in terms of shape of the doping profile, surface doping concentration, junction depth, sheet resistance and removal of the boron-rich layer（BRL）. In the aspect of BRL removal, three different methods were adopted to investigate their influence on device performance. The results demonstrate that our proposed chemical etch treatment（CET） with the proper etching time could be an effective way to remove the BRL.After removal of the BRL, Al;O;/SiN;stacks are deposited by atomic layer deposition（ALD） and plasma-enhanced chemical vapor deposition（PECVD） to passivate the cell surface. It was found that a reasonably-high implied Voc of 680 mV has been achieved for the fabricated n-type Si solar cells.
基金Project supported by the National Natural Science Foundation of China and the Chinese Academy of Sciences.
文摘A successful experimental synthesis of pure crystalline β-and α-C3N4 films on Si( 100) substrate was carried out by bias-assisted hot filament chemical vapor deposition (bias-HFCVD). It is found that a mixed-phase C3-x-Six-Ny buffer layer was formed between the Si substrate and the C-N film. A "lattice match selection" was proposed to study the growth mechanism of C3N4 clusters composed of many crystal columns with hexagonal facets.
基金National Natural Science Foundation of China (51964035)Natural Science Foundation of Inner Mongolia Autonomous Region (2019MS0520)Natural Science Foundation of Inner Mongolia Autonomous Region (2020LH05017)。
