Leybold Optics GmbH

Phoebus Lab Tool - The perfect instrument for layer stack and cell performance evaluation for Silicon Thin Film amorphous / microcrystalline (a-Si/µc-Si) tandem solar cell R&D environments

Based on the excellent performance in terms of layer uniformity and repeatability of the PHOEBUS production tool and a strong demand from the market, Leybold Optics designed and already delivered lab tools for research and development purposes for Silicon thin film PV applications.

The lab tools concept is strongly comparable to the PHOEBUS production tool in terms of the most important electrode’s design, however, restricted to substrate dimensions of 300 x 300 mm. Furthermore the lab tool uses a decreased grade of automation as well as carriers. This allows the parallel coating of a variety of smaller substrates and shapes when needed or e.g. the usage of different probe materials under same process conditions.

Phoebus PECVD Lab Tool
In difference to PHOEBUS production tool the lab tool concept is an in-line one as the process chambers are serially interconnected to each other. Corresponding gate valves located at the entrance and exit flanges of every individual camber avoid cross contamination between adjacent process chambers.  

Questions, inquiries, comments?
Get in touch with us at 

Telephone: +49 351 86695-112 and -83
E-mail: sales.photovoltaics@leyboldoptics.com

According to the man machine interface of PHOEBUS systems, the lab tool offers an almost endless variety of process configuration possibilities and programmable process sequences, as all process steps are not fixed within one PLC program. In fact almost any kind of machine control like movements, amounts of gas flow and settings of the plasma RF generator is driven by parameters that are editable within corresponding recipes. Of course these recipes can be stored either on the machine’s hard disc drive or exported to other storage media or edited separately from the lab tool. In such an endless number of recipes can be not only created and used again when needed e.g. in case deposition trials need to be repeated at a later time but prepared upfront, too, e.g. as a guideline for scheduled test sequences.

Of course the lab tool can be equipped with same cleaning capabilities by using of greenhouse friendly gas Flour (F2) as the PHOEBUS production tool. Here the process expert can select whether the cleaning and chamber conditioning procedures should take place automatically or triggered manually when needed.

By using the PHOEBUS lab tool and due to its excellent flexibility and ease of use, process expert are provided with a perfect tool for their research and development objectives for the deposition of any kind of Silicon based thin film layers and independently whether these have to be doped, need to be intrinsic or grown in amorphous or crystalline form paired with a high reproducibility that is a must for R&D or process development purposes.

Customizable design

As R&D and process development objectives often vary from customer to customer, the lab tool can be customized in accordance to individual needs. This is
not only true with regards to the amount of chambers that are to be connected in line. 

In fact Leybold Optics offers the possibility e.g. to enlarge the single chambers in case space for an additional amount of measuring tools to be implemented is required.

The picture on the right hand side does only show an example of the large variety of possibilities in machine setup.


  • Customizable and modular design features the manufacturing of:
    • single junction cells (a-Si or µc-Si)
    • tandem junction cells (a-Si/µc-Si or a-Si/a-Si)
    • multiple junction cells (triple junction cells,…)
    • single layers (interreflective, buffer..)
  • Substrate handling via carrier
  • Uninterrupted vacuum during entire process
  • Stable substrate temperature during processing and transportation
  • Easy access to each single reactor for maintenance purposes
  • Greenhouse friendly cleaning of process chambers by means of Fluor (F2) integrated in the system’s processing scheme 
  • Excellent gas separation between the individual process chambers avoiding any cross talk between process chambers
  • Extraordinary uniform layer deposition for amorphous and microcrystalline layers in special
  • Substrate handling automated throughout entire system
  • Ease of expansion and adaptation to key up with technology changes
  • Excellent maintenance and service accessibility
  • Robust design to achieve superior equipment life time
  • Service, PLC updates and other controls via remote access
  • Ease of transfer of parameter setting towards PHOEBUS production tool
    • possibility for cross check of process results and transition to standard production environment via Leybold Optics’ large area coating tool installed in Alzenau / Germany

Technical Data:

  • Dimensions (incl. maintenance areas): depending on customers request
  • Min. room height: 3 m
  • No clean room class required
  • Size of substrates: 300 x 300 mm or smaller
  • Substrate thickness: 2 … 5 mm
  • Customizable amount of process chambers connected in line to each other
  • Vertical (95°) overhead orientation of the substrate
    • avoids particle contamination on substrate surfaces 
    • no defects and shunts caused by deposition process
  • Process setting via recipe handling system
  • Data tracking for every substrate optionally available
  • Data exchange to MES system
  • Manual loading / unloading of samples by fixation on corresponding carrier