The PV solar cell lab is offering fabrication and characterisation of mono-crystalline silicon solar cells with state-of-the-art equipment. As such, it is well-suited to evaluate and process both standard and new materials in the silicon solar cell value chain: evaluation of silicon wafer material, novel wet chemical processes, advanced diffusion, surface passivation dielectrics and metallisation schemes. The versatility of the equipment allows both process improvement for standard silicon solar cells as well as development of advanced cell technologies. Simulation expertise at process and cell level is also available. Statistical methodologies for continuous improvement of the critical cell parameters have been developed. All technologies are developed and applied on industrial M2-sized silicon solar cell wafers.

Philip Pieters

Contact

Philip Pieters

Business Developer Solar at EnergyVille/imec
Description
Technical Notes

Advantages

The combination of a very experienced team of silicon PV specialists and an advanced equipment park provides the ideal environment for silicon solar cell technology development. Imec has a proven track record during several decades for fabricating state-of-the-art industrial-size silicon solar cells. Advanced concepts like n-type, bifacial , hetero-junction and epitaxial silicon cell technology is available. A methodology for continuous improvement of cell efficiency in combination with a critical cost of ownership analysis is the cornerstone of our advanced and industry oriented silicon solar cells developments.

Applications

Low-cost and industry-compatible processing developed for the fabrication of wafer-based crystalline-Si solar cells or similarly applied in thin-film technology context:

  • Wet chemical processes (Cost-efficient cleaning and Texturing)
  • Boron and Phosphorous diffusion / epitaxial growth
  • Dielectric passivation (SiO2, Si3N4, Al2O3, a-Si)
  • Laser ablation and doping
  • Metallisation schemes (screen printing, plating, ink jet, sputtering)
  • Selective contacts (Metal Oxide or Poly-Si based)

In-depth testing of the optoelectronic performance of wafer and cells :

  • Optical inspection
  • Dark/Light IV and parameter (series resistance, shunt resistance, J02,...) extraction
  • Photo- and electroluminescence (PL/EL)
  • Internal and external quantum efficiency (IQE/EQE)
  • Reflection/transmission (R/T)
  • Broad characterisation capabilities comprising e.g. TEM, SEM, SSRM, ....
  • SunsVoc (dependency of Voc on irradiance intensity)
  • Sheet resistance
  • Contact resistance
  • ICPMS to detect impurities on the wafer surface

Customers

  • PV cell and module manufacturers
  • Material suppliers
  • Equipment vendors
  • Companies looking for dedicated, innovative solar cell processing
  • Wet chemical processing tanks for 50 wafer cassettes for low Cost of Ownership
    • Advanced alkaline based texturing (single and both side)
    • Novel surface cleaning solutions
    • Full process control due to metal impurity surface inspection by Inductively Coupled Plasma Mass Spectrometry
  • Diffusion tubes for POCl3 and BBr3
  • Dielectric layer passivation
    • Spatial ALD Al2O3
    • Thermal SiO2, PECVD SiO2
    • PECVD Si3N4
    • PECVD a-Si
  • Laser ablation and doping
    • Laser openings lines or dots
    • Laser doping for selective emitter or back surface field
  • Metallisation schemes
    • Fine line screen printing with alignment Ag, Al
    • Electro-less, light induced and electro-plating of Ni, Cu, Ag
  • Optical inspection
    • Large-area high-resolution (<0.2 mm) inspection with optional automation and stitching
    • Small-area microscopy for optical (and SEM) inspection of detailed areas or cross-sections
  • Light IV
    • Cell tester up to 5 busbars
    • Cell tester for busbarless cells
  • Quasi Steady State Photo Conductance and PhotoLuminescence measurement to evaluate minority carrier lifetime and saturation current density
  • External quantum efficiency (EQE) scanning for accurately determining spectral electrical sensitivity of devices in 280-1200 nm range
  • Reflection (R) scanning for accurately determining spectral reflective sensitivity of devices in 280-1200 nm range
  • Sheet resistance measurement with ShereScan
  • Contact resistance extraction from Transfer Length Method