Compound Semiconductors / LED

LEDs (Light Emitting Diodes) are highly efficient illumination systems that are based on compound semiconductors and manufactured in a similar way. The costs for manufacturing LEDs vary considerably depending on output and yield achieved and on the luminence. In producing high quality LEDs, a number of processes are required that in turn entail demanding requirements for production facilities. One example are the thin, fragile sapphire wafers used, which require special thin wafer handling. Due to the high cost of sapphire, the industry is investigating solutions based on silicon, which would make available new processing options.

The solutions offered by SUSS MicroTec are used at three stages of the process:

Structuring of Substrates

To achieve an optimum surface structure, the wafer substrate is prepared prior to epitaxy (usually through coating with gallium nitride). The higher the quality of the surface structure, the greater the luminescence of the diode. Lithography and imprinting techniques are used for structuring the wafer.

Process Technologies

TechnologyProduct
Spin Coater, Spray Coater
Mask Aligner, Projection Scanner
MA/BA8 Gen3, MA/BA6, MJB4
Developer

Structuring of LED Chips

Just as with semiconductor manufacturing, LED production requires lithographic processing to achieve the microstructure. Special techniques to achieve enhanced luminous efficacy, such as imprinting with reflecting layers and photonic crystals, are used as well.

Process Technologies

TechnologyProduct
Spin Coater, Spray Coater
Mask Aligner, Projection Scanner
MA/BA8 Gen3, MA/BA6, MJB4
Developer
Wafer Bonder
XBS300

Packaging of LED Chips

As in the semiconductor industry, the reduction of manufacturing costs is a major driver for innovation. While wafer level packaging is a standard procedure for many applications, most of the processing steps in LED manufacturing take place after the wafers are singulated into chips, i.e. at die level. Wafer level packaging in LED manufacturing is still very much in the developing stage, yet this technology promises tremendous potential.

After singulation, LED chips are usually placed on another board or wafer for additional processing (fan-out technique). As silicon comes to be used in this process, other techniques are becoming viable as well, such as the creation of TSVs, which are already being applied in 3D integration.

Process Technologies

TechnologyProduct
Spin Coater, Spray Coater
Mask Aligner, Projection Scanner
MA/BA8 Gen3, MA/BA6, MJB4
Developer
Wafer Bonder

Product Finder & Contact