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Fraunhofer Institute for Electronic Nano Systems

Atomic Layer Deposition (ALD) and Targeted Application Areas

Atomic Layer Deposition (ALD) has been an active area of research and development at Fraunhofer ENAS together with the Center for Microtechnologies at TU Chemnitz since 2006. Starting with processes for copper oxide and copper, further materials are continuously implemented for a variety of application areas.

Available Equipments

  • 100 mm single-wafer tool with two BRONKHORST liquid delivery systems and two home-built bubblers
  • MicroSystems 200 mm multi-chamber tool with two ALD chambers currently under ramp-up. Each ALD chamber is each equipped with:
  • Two KEMSTREAM direct liquid injection systems
  • Two BRONKHORST liquid delivery systems
  • Variety of special gases
  • Possibility of thermal and remote plasma ALD

The MicroSystems 200 mm cluster system further includes in-situ XPS and Raman spectroscopy for direct analysis of the samples without vacuum break. Furthermore, a CVD chamber for carbon nanotubes (CNTs) and a chamber for ion-beam sputtering/etching to deposit standared metal films are available on the tool. All chambers, including the analytics, are fully 200 mm capable.

MicroSystems 200 mm cluster system (left) and detailed view of an ALD process module (right).

ALD Materials and Application Areas

1. Metals

Copper

  • Seed layers for metallization of nanoelectronic interconnect systems and trough-silicon vias (TSVs) in 3D integration
  • Functionalization of CNTs and CNT integration in metallization systems

Nickel

  • Liner for interconnect systems
  • Seed layers for TSV metallization
  • Functional films in magnetic/spintronic film systems
  • Functionalization and metallization of CNTs

2. Metal Oxides

Copper Oxide

  • Intermediate stage for ALD of copper
  • Functionalization of CNTs, e.g. for sensors

Nickel Oxide

  • Intermediate stage for ALD of nickel
  • Functional films in magnetic/spintronic film systems
  • Functionalization of CNTs, e.g. for sensors

Aluminum Oxide

  • Passivation layer, e.g. for MEMS, electronic devices, solar cells
  • Dielectric with high permittivity, e.g. for storage/memory applications
  • CNT functionalization

3. Metal Nitrides / Carbonitrides

Titanium(carbo)nitride and Tantalum(carbo)nitride

  • Diffusion barriers against copper diffusion in nanoelectronic interconnect systems and TSVs for 3D integration
  • Electrode material in conjunction with high-k oxides
  • Hard coatings / abrasion protection for MEMS

At least one of these two nitride / carbonitride materials will be implemented at the MicroSystems 200 mm cluster system.

Please click for Selected Publications and Patents

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