Effect of High-Temperature Annealing on Ion-Implanted Silicon Solar Cells

Abstract

P-type and n-type wafers were implanted with phosphorus and boron, respectively, for emitter formation and were annealed subsequently at 950∼1050∘Cfor 30∼90 min for activation. Boron emitters were activated at1000∘Cor higher, while phosphorus emitters were activated at950∘C. QSSPC measurements show that the impliedVocof boron emitters increases about 15 mV and theJ01decreases by deep junction annealing even after the activation due to the reduced recombination in the emitter. However, for phosphorus emitters the impliedVocdecreases from 622 mV to 560 mV and theJ01increases with deep junction annealing. This is due to the abrupt decrease in the bulk lifetime of the p-type wafer itself from 178 μs to 14 μs. PC1D simulation based on these results shows that, for p-type implanted solar cells, increasing the annealing temperature and time abruptly decreases the efficiency (Δηabs=−1.3%), while, for n-type implanted solar cells, deep junction annealing increases the efficiency andVoc, especially (Δηabs=+0.4%) for backside emitter solar cells.

Damage Induced by Neutron Radiation on Output Characteristics of Solar Cells, Photodiodes, and Phototransistors

“…Solar cells have attracted much attention as good candidates for low cost, good stability, and high efficiency. There are many researches in this emerging technology in order to investigate the behavior of solar cells in various working conditions [26][27][28][29]. Solar cells have proved to be very reliable devices regardless of the environment in which they exist.…”

Influence of boron clustering on the emitter quality of implanted silicon solar cells: an atom probe tomography study

“…Theoretical calculations in Reference [10] suggested that because of interaction of B atoms and free Si, boron interstitial clusters (BICs) may form during ion implantation and thermal annealing. This results in incomplete activation rate in these emitters [8,11], especially for insufficiently high thermal budgets [12]. For sufficiently high thermal budgets, as is the case in this study, BICs dissolve completely or are undetectable by transmission electron microscopy [13,14].…”

“…B signal obtained is well resolved as it is unaffected by the large tail of Si ions increasing accuracy of results. B peak here is obtained only at 11 (B + ) and 5.5 (B ++ ) amu because of the implantation process, whereas the BCl 3 diffusion process exhibits 4 peak at 5, 5.5, 10, and 11 amu corresponding, respectively, to 10 B ++ , 11 B ++ , 10 B + , and 11 B + ions. C + and CH + ions emerge because of surface contamination of the tip in SEM/focused ion beam chamber during tip preparation.…”

Radiation Hardness Study of Silicon Carbide Sensors under High-Temperature Proton Beam Irradiations

“…However, high-temperature (500 °C and above) implantations hinder this effect, thanks to a dynamic annealing process occurring under these conditions. More details regarding ions implantation at high temperature in silicon carbide can be found in [ 2 , 3 , 4 , 5 , 6 , 7 ]. Consequently, aware of the good functionality of SiC above 500 °C and of the high temperature condition needed during ion implantations, it may be a valid solution, for some applications in extremely harsh environments such as within fusion reactors core vessels, to employ SiC sensors at high temperatures to make them more radiation tolerant.…”