PERC stands for passivated emitter and rear cell. Together with Al-BSF, it is one of the most widely used crystalline silicon cell types in industry. A bifacial PERC cell has, from front to back, an anti-reflective coating, an n+ emitter, a p-type base and a rear dielectric stack. That stack may contain AlOx, SiOx or SiNx, and the AlOx carries a negative charge that pushes minority electrons away from the rear surface. The rear of a bifacial PERC cell is especially prone to polarisation-type potential-induced degradation. When the cells sit at negative voltage to ground, positive charge drifts through the encapsulant, which increases recombination at the rear and lowers current and voltage. Field tests found this degradation in PERC modules biased at negative system voltage within several weeks. Modules biased at positive voltage did not show it. Adding SiOx to the rear stack partly reduces the effect. Using a more resistive polyolefin encapsulant or a polymer backsheet instead of EVA and glass is a more certain fix, and the IEC 62804-1 test methods are used to check susceptibility. Bifacial PERC cells with localized rear contacts are more prone to cracking and corrosion under thermal cycling. However, many cracks do not cause power loss, and multi-wire PERC modules lose little power per cracked half-cell. PERT and TOPCon cells have a p+/n front, which is more sensitive to polarisation than the n+/p front of PERC.
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subclass_ofc1 drafted · lead Crystalline silicon PV
Al-BSF and PERC are named as the most common industrial crystalline silicon cell types.
sec=h56 h=8d42c4699ab3review note: support check: partial - Passage names Al-BSF and PERC as the most common cell types and mentions crystalline silicon cells, but never explicitly states PERC is a kind of crystalline silicon PV.
related_toc2 drafted · lead Solar cell
PERC is a solar cell architecture.
sec=2.3.1 h=3a65ff4976bcsec=h56 h=8d42c4699ab3c3 drafted · lead Potential Induced Degradation (PID)
The rear side of bifacial PERC cells is especially prone to polarisation-type PID (PID-p) under negative bias.
sec=2.3.1 h=3a65ff4976bcfig=21 h=d8cf6c55256fc4 drafted · lead Cell Cracks
Bifacial PERC cells with localized rear contacts are more prone to degradation from cracking and corrosion under thermal cycling.
sec=h56 h=8d42c4699ab3tbl=7.r5 h=0a21fb8dc566c5 drafted · lead Anti-reflective coating
The cell stack runs from front to back as ARC/n+/p/ARC, and the rear dielectric may be AlOx, SiOx or SiNx.
sec=2.3.1 h=3a65ff4976bcc6 drafted · lead Alternative encapsulant material
A more resistive polyolefin-containing encapsulant instead of EVA is a more certain PID-p mitigation.
sec=2.3.1 h=3a65ff4976bcc7 drafted · lead IEC 62804-1 proposed
This is the PID test standard for crystalline silicon modules. The 2025 edition adds UV-illuminated methods for PID-p.
sec=2.3.1 h=3a65ff4976bcreview note: support check: partial - Passages describe IEC 62804-1 test methods for c-Si modules and 2025 UV methods for PID-p, but not explicitly that PERC relates to it as 'the' standard; mostly supported though.
c8 drafted · lead TOPCon cell
TOPCon and PERT have a p+/n front, which is more sensitive to polarisation than the n+/p front of PERC.
sec=2.3.2 h=a3572257e49ac9 drafted · lead Half-cut cells
fig=40 h=d8f9ab4a58detbl=7.r5 h=0a21fb8dc566review note: support check: partial - Passages mention PERC half-cell modules and PERC half-cell cracking, but no explicit relation stated beyond that.
c10 drafted · lead Light Induced Degradation (LID)
In combined stress testing, a smaller amount of LID was mixed in with PID-p.
sec=2.3.1 h=3a65ff4976bctypical_power_lossc11 disputed nominal 0.2 PERCENT
Conditions: Multi-wire PERC modules, per half-cell with dendritic-like cracking
tbl=7.r5 h=0a21fb8dc566conflicts with: PERC cell (c13)
c12 drafted · lead ≤ 10 PERCENT
Conditions: Relative degradation from PID-p in glass/glass PERC modules with EVA after combined-accelerated stress testing at -1200 V bias, flash tested from the front at STC
sec=2.3.1 h=3a65ff4976bcreview note: support check: partial - Passage says 'almost 10%' relative degradation from the front, not 'up to 10%'; conditions otherwise match.; possible conflict with c13 (same source; check the conditions); review: partial - The passage gives 'almost 10%' relative degradation from one combined-accelerated stress test at -1200 V, flash tested from the front, so a 10% ceiling fits that result, but calling it a 'typical' power loss for PERC cells goes beyond a…
Conditions: Same combined-accelerated PID-p stress test of glass/glass PERC modules with EVA, flash tested from the rear at STC
sec=2.3.1 h=3a65ff4976bcreview note: possible conflict with c12 (same source; check the conditions)conflicts with: PERC cell (c11)
related_to c5related_to c3related_to c3