Solar Cell Manufacturing

wafer · TOPCon · back contact · US cell plants

The cell is where a silicon wafer becomes a power device, and China makes more than 80% of the world's cells. The US built module lines first and is only now building the cells to fill them.

Two panels. Top: US solar manufacturing capacity by stage - modules more than 66 GW, cells about 11 GW, ingots and wafers near zero. Bottom: a TOPCon cell cross-section, top to bottom: silver front contacts, silicon nitride anti-reflection coat, p+ boron emitter, n-type monocrystalline wafer about 130 microns thick, a tunnel oxide about 1.5 nm thick, n+ doped polysilicon forming the passivated contact, rear silicon nitride, and silver rear contacts. US SOLAR MANUFACTURING CAPACITY BY STAGE Modules 66+ GW Cells ~11 GW Ingots and wafers near zero INSIDE A TOPCON CELL (NOT TO SCALE) Silver front contacts Silicon nitride anti-reflection coat p+ boron emitter n-type monocrystalline wafer, ~130 microns Tunnel oxide, ~1.5 nm n+ doped polysilicon (passivated contact) Rear silicon nitride Silver rear contacts
Leading architecture
TOPCon
PERC share, 2025
~14%
US cells vs modules
~11 vs 66+ GW
Hub
Energy

Finding

TOPCon has replaced PERC as the mainstream cell, and the US has five times more module capacity than cell capacity

ITRPV puts PERC at about 14% of 2025 production, with TOPCon the dominant architecture and back contact (BC) rising behind it. In the US, module lines passed 66 GW on the 45X production credit while cell capacity is about 11 GW, so most US-assembled panels still use imported cells.

Cell manufacturing is a semiconductor process run at enormous volume: texturing, boron and phosphorus diffusion, deposition of passivation layers, screen-printed silver metallization, firing, and flash testing and binning. A half-point swing in yield or efficiency moves cost per watt more than most supply contracts. TOPCon won because it reuses much of a PERC line's diffusion and printing equipment while adding a tunnel oxide and doped polysilicon layer at the rear; heterojunction (HJT) needs a fully new low-temperature line, and back contact moves all metallization to the rear for higher efficiency at higher process cost.

Silver is the largest non-silicon cost in a cell, which is why LONGi, Aiko and others are pushing copper plating and silver-reduced pastes. The next step is perovskite-on-silicon tandem: LONGi holds lab records above 34%, and ITRPV expects mass production around 2027.

Architectures

Four silicon cell architectures, one thin-film alternative

Ranked by current market weight.

Solar cell architectures
ArchitectureHow it differsStatusLeading makers
TOPConTunnel oxide plus doped polysilicon passivated rear contact on an n-type waferDominant since 2024; upgrade path from PERC linesJinkoSolar, Trina, JA Solar, Tongwei, Drinda
Back contact (BC)All contacts on the rear; no front shading from silver fingersPremium share rising; ITRPV sees up to 28% by 2036LONGi (HPBC), Aiko (ABC), Maxeon
Heterojunction (HJT)Amorphous silicon layers on crystalline wafer; low-temperature processNiche; high efficiency, higher capex and silver useTongwei, Huasun, Risen, REC
PERCPassivated rear on p-type wafer; the previous mainstreamAbout 14% in 2025 and fadingLegacy lines in China, India, Southeast Asia
CdTe thin filmCadmium telluride deposited on glass; no wafer or cell stepThe main non-silicon route at scaleFirst Solar
Perovskite-silicon tandemPerovskite top cell stacked on a silicon bottom cellPilot lines; mass production expected around 2027LONGi, Oxford PV, Hanwha Qcells, GCL

Global makers

China makes most of the world's cells

Representative manufacturers; capacity changes fast in a market running about three times demand.

Global solar cell manufacturers
ManufacturerHome baseCell linesNotes
LONGiChinaBC (HPBC 2.0)Largest wafer maker; moved its cell roadmap to back contact
TongweiChinaTOPCon, HJTLargest pure cell producer and a top polysilicon maker
JinkoSolarChina, Southeast Asia, US module plant in FloridaTOPConAmong the largest module shippers
Trina SolarChina, Southeast AsiaTOPCon (i-TOPCon)Sold its Texas module plant to T1 Energy in December 2024
JA SolarChina, Southeast Asia, OmanTOPConBuilding outside China for tariff access; sold its Arizona module plant to Corning in 2025
AikoChinaBC (ABC)Copper-metallized back contact
Hanwha QcellsSouth Korea, Malaysia, Georgia (US)Silicon cells; tandem pilotBuilding the first large US ingot-to-module chain at Cartersville, Georgia; ramp slipped into 2026
Waaree, Adani, Premier EnergiesIndiaTOPCon, PERCIndia adding cell capacity behind domestic-content rules
First SolarUS, Malaysia, Vietnam, IndiaCdTe thin filmNo silicon cell step; see Solar Panels

US plants

US cell plants are restarting the stage that disappeared

Cell production restarted in 2024 after a five-year gap.

US solar cell plants
ManufacturerSiteTechnologyStatus
SunivaNorcross, GeorgiaSilicon cellsRestarted cell production in 2024
Hanwha QcellsCartersville, GeorgiaIngot, wafer, cell, moduleRamping the integrated chain
ES FoundryGreenwood, South CarolinaSilicon cellsOpened in 2025
T1 EnergyG2 Austin, Rockdale, Milam County, TexasTOPCon cellsUnder construction; first cells planned for early 2027
Silfab SolarFort Mill, South CarolinaSilicon cellsCell line under construction
Canadian SolarJeffersonville, IndianaSilicon cellsCell plant built to feed its Mesquite, Texas module plant; first output 2026
First SolarOhio, Alabama, LouisianaCdTe thin filmIntegrated module plants; no separate cell step
Boviet SolarGreenville, North CarolinaTOPCon cellsCell plant in phase two, beside its module plant

Sources

Sources and scope

Scope
Solar Cell Manufacturing
Sources
ITRPV 17th edition (VDMA, 2026); PV Tech Research US capacity; company announcements; AustinIO
Updated
October 2026