Nanofabrication and Analysis

The Nanofabrication and Analysis group performs semiconductor preparation processes for silicon and other semiconductor materials, like GaAs, SiC, Ge and diamond. Activities include pre- and post-ion beam implantation lithographic processing, wet and dry etching of devices, deposition of materials, as well as, different analytical and electrical investigations. The group is a one-stop-shop providing start-to-finish processing or any intermittent steps. The group serves the needs of the IBC, HZDR and industry, as well as, the wider scientific community as a user facility. 

The cleanroom assists in enabling the various research topics of the Institute of Ion Beam Physics and Materials Research including  Nanostructures, Optoelectronic Materials, Nanomagnetism, Transport in nanostructures and Doping & Defects in Semiconductors.

Cleanroom Introduction

New users, and those who wish to use the cleanroom can do the Cleanroom Introduction online. This is the first step on your journey to using the cleanroom. 

Instruction Portal ->  Occupational safety -> Repeated briefing -> FWIO - Cleanroom 711/105

Note: the test is only available internally.

Useful Forms:

All samples processed in the cleanroom are required to have a processing template. This is commonly known as a process flow. These are currently managed through the process approval section of the Nanofaro Wiki.

However, if one only requires short work to be done in the cleanroom you can fill in one of the following forms and bring it to Ciaran Fowley or the relvant staff member. Processing is then be handled by the cleanroom staff. The forms are also available on the NanoFaRo Wiki under Useful Forms.

• Wet chemistry : For chemistry processes, e.g. Piranha, buffered oxide etching, KOH etching
• Photolithography : For UV lithography with photomasks, otherwise known as microfabrication
• Deposition : Material deposition by evaporation (e-beam and thermal) and sputtering
• Reactive Ion Etching : Reactive ion etching with SF6, CF4, O2 and C4F8 
• Thermal Processing : For thermally grown oxides, annealing and rapid themal annealing / processing

Note: the forms are only available internally.

Services and methods:

Clean Room

The cleanroom provides an area of 320 m² of Class 500,000 or better, within which a total of 40 m² is Class 100 work space. It is located adjacent the implan­ter halls.

Wet chemistry

Chemical pre­paration of clean surfaces via solvent and acid (Piranha, RCA-1, RCA-2 etc.) processes is available. Selective etching of Si, SiOx, Al, GaAs and Ge is available.

Photolithography

Photolithography with a resolution below 2 µm o­ver a 150 mm wafer is available as well as direct laser writing possibilities. A large variety of existing photomasks can help you accomplish your patterning fast.

Reactive Ion Etching

Inductively coupled plasma reactive ion etching of Si, SiOx and various 2D materials is possible in continuous as well as cycled (Bosch-Process) processes with thickness monitoring.

Thin Film Deposition

Physical deposition of a myriad metals, semi-conductors and oxides via both sputtering and evaporation is possible. A total of 12 electron beam pockets, 2 thermal sources and 4 sput­ter targets are available.

Measurement techniques

Optical inspection, thickness measurements and electrical characterisation in the cleanroom mean fast calibration of deposition, oxidation and etch processes all with the clean environment

Group information:

The preparation equipment in the Class-100 cleanroom incorporates:

• Processing Technologies
  • Piranha, RCA1, RCA2, and solvent cleaning up to 6"
  • Anisotropic and isotropic material etching, BHF, HP3O4, TMAH, KOH, Al-etch up to 6"
  • Front and back side UV lithography up to 6"
  • ICP reactive ion etching, anisotropic and isotropic etching of Si, SiC, SiO2 etc. up to 6"
  • Thermal oxidation, diffusion and annealing in precision furnances (1050°C in O₂/HCl, Ar/H₂, H₂O) up to 6"
  • Rapid thermal processing (annealing and oxidation up to 1050°C for 600 s) up to 4"
  • High Temperature vacuum annealing
     
• Thin Film Deposition
  • Sputtering: DC- and RF-magnetron sputtering of Al, Si, SiO₂, Ge, AlSi (other materials are available) up to 6"
  • Evaporation: 12 pocket E-Beam, 2-pocket thermal evaporator for evaporation of Cr, Au, SiO, Mn, Pt, Ti, Al, Ni, NiFe, CoFe....) up to 4"
      
• Device Packaging
  • Ultrasonic wire bonding with Au and Al wires

• Measurement and Characterization
  • Interferometric thicknesses measurements of resist, oxide, SOI thicknesses. Ellipsometry is also available
  • Optical microscopy with resolution down to 1µm measurement
  • Dektak profilometry 
  • Atomic force microscopy (AFM)
  • Electrical measuring techniques (I/V-, MIS-C/V-measurement)
     
• Computer Aided Design
  • Assistance for mask layout design for photolithography (AUTOCAD/GDSII)