Fragmented supply
Epitaxy, chip processing and CIC assembly usually come from three different suppliers. Every interface is a separate qualification and a separate schedule risk.
32%
peak BOL efficiency
4080 CIC
III–V epitaxy · Space photovoltaics · Xiamen
Power that
Power that
survives the orbit
Wafertop grows, processes and assembles triple-junction GaAs solar cells — 30 to 32% BOL efficiency, qualified to GJB 7392-2011, built at up to a million epitaxial wafers a year.
1,000,000
Epi wafers / year
4-inch equivalent
4-inch equivalent
13×
Aixtron MOCVD
2800 G4
2800 G4
25+
Years of epitaxy
on the founding team
on the founding team
The problem
An array is decided
An array is decided
before the first cell ships
Four things determine whether a photovoltaic programme holds its schedule and its power budget. None of them is a cell-level specification — they are supply-chain properties.
Batch-to-batch drift
Efficiency spread across lots does not stay at cell level — it becomes array-level power loss, discovered late at panel integration.
Radiation margin
End-of-life power sizes the array, not beginning-of-life. Without published 1 MeV degradation data, that margin is guesswork.
Volume, not samples
A constellation needs tens of thousands of cells on a repeatable schedule. Qualification lots are not a capacity plan.
Quick facts
Six numbers that describe the plant behind the datasheet.
Efficiency
Lattice-matched AlGaInP/InGaAs/Ge triple junction, in mass production — not a laboratory result.
30 – 32% BOLEpitaxy capacity
800,000 to 1,000,000 four-inch-equivalent wafers a year across thirteen Aixtron MOCVD 2800 G4 reactors, supplemented by leased tools.
1,000,000 wafersChip capacity
A complete in-house solar-cell line — 200,000 to 240,000 chips a year: lithography, etching, coating, thinning, dicing and test.
240,000 chipsWafer sizes
Ge substrates in 4-inch and 6-inch, with 6 µm epitaxial layers and EPD below 300/cm².
4" & 6"Heritage
Founding team with programmes for the Chinese Space Station, lunar rovers and satellite power systems.
25+ yearsQualification
Every space cell type in this catalogue is fully qualified to the national space standard.
GJB 7392-2011
Product portfolio
One chain, from epi
One chain, from epi
to assembled cell
We are the single supplier for the three steps that usually take three vendors — which is the answer to problem 01 above.
Triple-junction cells & CIC assemblies
Lattice-matched AlGaInP/InGaAs/Ge on Ge, delivered bare or as a finished CIC — 4080 or 14468 — with coverglass, interconnectors and bypass diode.
- Efficiency
- 30 – 32% BOL
- Cell area
- 30.2 – 79.8 cm²
- Standard
- GJB 7392-2011
Thin-film flexible cells
AlGaInP/GaAs/InGaAs lifted off the growth wafer — 31.5% on polyimide, 30.5% on metal substrate — for platforms where specific power sets the mission.
- Efficiency
- 30.5 – 31.5% BOL
- Specific mass
- 20 – 28 mg/cm²
- Thickness
- 30 – 75 µm
Solar cell epitaxial wafers
4-inch and 6-inch Ge-based wafers for customers running their own cell process, or needing a custom design on a qualified stack.
- Efficiency
- 30.8% BOL
- Substrate
- Ge, 4" / 6"
- EPD
- < 300 /cm²
Assembly components — coated coverglass (Tave ≥ 93.5%), Si bypass diodes and space-grade interconnectors — are supplied with the cell or separately. See components →
Product imagery is derived from photographs of our own hardware and restaged for presentation. Minor visual detail may differ from delivered parts — the tabulated dimensions and electrical data are the binding reference.
Key technology
Three properties decide what a cell delivers at end of life — not what it measures on the flash tester at beginning of life.
-
01
Lattice-matched triple junction
GaInP / GaAs / Ge sub-cells joined by tunnel junctions, each absorbing a different band of the spectrum — grown in-house on our own MOCVD reactors.
-
02
Published radiation margin
1 MeV electron degradation and temperature coefficients are part of the datasheet, so end-of-life power can be calculated rather than assumed.
-
03
Thin-film lift-off
Flexible cells at 30 µm and 28 mg/cm² — the same epitaxy, released from the growth substrate onto metal foil.
Applications
From GEO telecom platforms to CubeSat deployables and high-altitude aircraft — the same epitaxy, tuned to the radiation and mass budget of each mission.
Constellation satellites
Repeatable batch performance and volume pricing for large flat-panel arrays.
Telecom & exploration
Radiation-hard triple-junction cells for 15-year GEO missions and deep-space probes.
CubeSats & smallsats
30 µm flexible cells at 28 mg/cm² for deployable and body-mounted arrays.
HAPS & UAV
Lightweight thin-film cells for high-altitude pseudo-satellites and long-endurance aircraft.
Company
Built in Xiamen,
Built in Xiamen,
qualified in orbit
Founded in 2021 and headquartered in Xiamen, Wafertop is a national high-tech enterprise focused on III–V compound semiconductor epitaxy, chip R&D and industrialisation. We hold ISO 9001 certification, and our cells are exported to customers across multiple countries and regions.
Beyond photovoltaics, the same MOCVD platform produces 940 nm VCSEL epitaxial wafers, edge-emitting lasers and InGaAs PIN/APD detector wafers.
Send us your array requirements
Cell size, orbit, radiation dose and annual quantity — we will come back with a specification and a price.
Request a quote