POCl3 Auto Refill System


HORIBA's Award Winning Fluid Delivery System (FDM Series) has revolutionised the POCl3 diffusion process by developing a system to automatically deliver bulk liquid POCl3 in 20 litre ETFE lined stainless steel canisters to multiple fixed plastic bubbler vessels.

The FDM and VM series are used for n-type diffusion layers as a dopant in manufacturing crystal silicon-based solar cell.
The system can also be used in the BBr3 diffusion process, improving process stability, increasing uptime, reducing logistics and labour costs and higher safety.


  1. Higher productivity
    The VM Series (Vapor Delivery Module) achieves higher productivity due to minimizing downtime as it does not require a traditional quartz bubbler exchange
  2. Reduced running costs
    The FDM Series reduces consumption of POCl3: up to 30% lower price per kg
    More than 99.8% uptime due to continuous production
    Decrease the cost of POCl3 waste
    Longer tool lifetime and lower maintenance costs due to the process line never being exposed to the atmosphere
    Delivered by 20L canister reduces logistics, storage and handling costs
    Fewer POCl3 exchanges and bottle returns result in lower labor costs
  3. Improved process stability
    The VM Series keeps the liquid level ”High” resulting in the pick-up rate being more stable than a traditional quartz bubbler
    There is no affect by liquid level due to the bubbler being continually refilled
    No bubbler exchanges are needed resulting in no exchange mistakes
    There is no affect from ambient temperature fluctuactions
    Sheet resistance is more stable than traditional bubblers resulting in improved sheet resistance repeatability and reproducibility.
  4. Improved safety
    No more quartz. The VM Series is made from PFA vessel which is much more robust than quartz, no handling, exchanges or refilling of quartz bubblers are needed as it does not require periodical exchanges resulting in less opportunities for human error.
    POCl3 is delivered in 20L ETFE lined stainless steel containers and contained in fixed and robust PFA vessel.
    Robust, leak tight bubbler housing with N2 blanket and connected to facility exhaust
    Integrated liquid leak and gas leak detection
    Wetted lines fully purged and leak checked automatically.
  5. Improved reliability
    POCl3 is hydrophilic and produces phosphoric acid which can cause corrosion or crystallization. A normal bubbler requires periodical exchanges and when a bubbler is exchanged the possibility of contact with air increases. The HORIBA POCl3 Auto Refill System does not require exchanges of the bubbler resulting in a very low chance that POCl3 tubing makes contacts with the air.

Manufactured by HORIBA


Liquids supported

POCl3, BBr3. Liquids compatible with pfa and ptfe

Process lines

4 x independent Coaxial, N2 purged process lines to deliver liquid to 4 x furnaces

Liquid line connections

All liquid line connections are housed inside cabinets that are connected to facility exhaust

Delivery distance limit

Total length of supply/return line 50m

Differential pressure sensor with alarm

Check for cabinet or Coaxial tubing leaks

Leak detection

Integrated liquid and gas leak detection

Over pressure protection

Safety burst disk

Supply method

Pressurise bulk canister

Bulk canister

Maximum 38 L (see diagram for dimensions)

Receiving system

Maximum 20 HORIBA VM Advanced Bubblers

Wetted parts


Pressure Measurement points

1.   Operation line 1 MPa(G) F.S.

2.   Purge line 500 kPa(G) F.S.

3.   Bulk canister and pressurised leak check of wetted parts 300 kPa(G) F.S.

4.   Vacuum leak test and purge check function 100 kPa(A) F.S.

Liquid removal method

Automatic N2 and vacuum cycle purge with automatic purge check function


EtherNET communication between refill system and HORIBA Advanced Bubbler VM

Bulk canister scale

0 to 100 kg (gross)


<60 dB (A) at 1 m

Working environment

15˚C to 35˚C ≤ 85% relative humidity


1200 mm


605 mm

Height (including light tower)

2635 mm


375 kg

Safety standards

CE, designed to SEMI S2

Power requirements

100~240 VAC 50/60 Hz 6 A ~ 12 A

 Canister Dimensions

Canister dimensions

Canister dimensions

*subject to change

Automatic Refill System (FDM 1100) Features:

  • Robust, sealed and exhausted housing
  • Cabinet differential pressure with alarm
  • Integrated gas leak detection
  • Touch panel user interface with remote access for troubleshooting
  • Lockable doors and slide out canister retainer with safety interlock
  • Canister scale
  • Integrated safety reservoir with liquid leak detection

Bubbler (VM) Features:

Liquid temperature is measured in the VM. The flow algorithm calculates the required carrier gas flow through the bubbler based on the measurement of temperature, pressure and vapor pressure.

  • Auto refill liquid shut off valve
  • Robust N2-rich sealed housing
  • Vision Panel
  • Lockable door
  • Fixed PFA bubbler vessel
  • Integrated high performance single board computer
  • Integrated safety reservoir with liquid leak detection