Laser Bar Bonding
Solid state lasers are versatile, light-emitting optical units which can be found in a variety of industrial applications. They combine the valuable physical characteristics of gas laser sources (beam conformity, coherency) with the advantages of solid state components (efficiency, small design, low voltage operation).
Typical applications include light sources for optical fiber communication, sensors, scanners, and as pumping sources for optical resonators of high power lasers. Further fields of use are found in medical appliances, marking, soldering, cutting and welding of various materials.
What are the challenges?
- Sensitive components with brittle materials and optically active areas
- No-touch zones on surfaces
- Delicate edges and facettes
- Perfect coplanarity required to ensure proper thermal management
- Void free bonding required
- Highest placement accuracy needed to guarantee coaxial position of single elements or defined overhang
- Solder materials tending to oxidation
- Large components exceeding the machine's field of view
- Face-up alignment
The Finetech Solution
Tools & Modules
- Automatic Bonding Force Modules apply optimal control of force
- Special tool shapes avoid touching forbidden areas
- Active and passive equalization tools guarantee even bond line
- Unique fixed beam splitter, in combination with rotating placement arm, eliminate placement error
- Numerous standard and custom enclosures provide AuSn and In joints with proper bonding atmosphere
- Mask tools, in combination with 2-point alignment, for face-up and relative alignment of large components
Step-by-step
Face-down alignment Laser to Substrate:
- Align laser's active surface pattern to glass mask pattern 1
- Pick up laser with glass mask tool
- Align substrate fiducials to glass mask pattern 2
- Place and bond laser
Relative alignment Photo Diode (PD) to bonded Laser:
- Align PD active surface pattern to glass mask pattern 1
- Pick up PD with glass mask tool
- Align laser active surface pattern to glass mask pattern 2
- Place and bond PD
Use process gasses like inert or forming gas in case of AuSn, or Formic Acid gas in case of Indium (In).
Process Gas Integration
- Process gas integration for AuSn and In bonding for oxide layer reduction
- self-sufficient formic acid gas generation
- Safe handling of fluid formic acid
- Sophisticated process gas enclosure with controlled injection and outlet
- Automatic control of activation time and concentration for reproducible results
Integrated Process Management (IPM)
Integrated Process Management (IPM)
Principle of process gas integration
Operating software for rework
Operating software for bonding
The Integrated Process Management (IPM) is the center piece of a FINEPLACER® system1 - the place where it all comes together. IPM is more than just thermal management. It synchronizes the control of all process modules and their related parameters:
- Controlled and precisely balanced interaction of top and bottom (pre-)heating and cooling
- Control of temperature, time, force, power, energy, flow
- Controlled process gas integration for reduced solder contamination, minimized surface tension effects and smooth spherical solder residues
IPM is very complex, yet easy to access. Via the GUI of the operating software, the user has perfect control of all required adjustments. Just drag 'n drop to define temperature ramps or activate process modules. All settings are represented in only one profile, making for a very intuitive work flow.
The operating software provides an ever-growing library of profiles for all kinds of processes. It also offers comprehensive data logging functions essential for statistical process control. This is as easy as process development can get.
