SDK study of LED crystal growth process: hybrid PPD process is expected to break the brightness limit

In order to meet the increasing market demand, Showa denko group (SDK) to fabricate a gallium nitride (GaN) and other new technology high quality nitride based compound semiconductor, mainly for the blue and white light emitting diode (LED).

This new process is called "hybrid PPD process", which is the combination of conventional metal organic chemical vapor deposition (MOCVD) and the plasma assisted physical deposition (PPD) process. PPD process for the generation of nitride based semiconductor crystals.

Using this new technology, we can produce high quality four inch epitaxial wafer (epitaxial wafer) which can not be produced by traditional metal organic chemical vapor deposition (MOCVD) process. Using the hybrid PPD process, Showa (SDK) has successfully developed the highest brightness blue light-emitting diodes on the market. Showa (SDK) will be launched this year in the blue light-emitting diode market.

Showa Electronics Group (SDK) has decided to build a production line in Chiba, Japan (Chiba) branch, the use of this new technology to produce four inch epitaxial wafer. Due to the adoption of new technology production out of the wafer is relatively large, coupled with the new production line, Showa denko group (SDK) blue light emitting diode production capacity will be greatly increased, the current monthly production capacity of 30 million, by the end of this year will be increased to 100 million per month.

A brief introduction to the new technology of mixed PPD

At present, GaN based blue or white light emitting diode (a nitride based compound semiconductor typical) lighting efficiency has more than other light sources (such as incandescent lamp, fluorescent lamp), but the mass production of new technology for high quality epitaxial wafer is still very necessary.

Showa Electric Group (SDK) hybrid PPD new process, can ensure a significant increase in efficiency, and can produce a better crystal quality four inch epitaxial wafer (epitaxial wafer).

At the same time, Showa denko group (SDK) of the hybrid PPD process in the epitaxial growth process based on the accumulated over the years, can produce high quality crystal layers; and the production efficiency than the traditional metal organic chemical vapor deposition (MOCVD) process is more high. Showa Electric Group (SDK) hybrid PPD process technology has applied for more than 30 patents.

According to the X ray rocking curve (XRC) analysis, using PPD technology to produce sapphire substrate, a single-crystal nitride layer formed in the above and using metal organic chemical vapor deposition (MOCVD) compared to similar products of production process, the crystallization quality showed significant improvement.

Term explanation:

Nitride based composite semiconductor

Based on (Alx, Gay, In1-x-y) N composite semiconductor, commonly used in the production of ultraviolet and green light-emitting diodes and blue laser diodes (LD). As a new type of electronic devices, these products are attracting more and more attention.

Gallium nitride (GaN) - based light emitting diodes

Depending on the composition, GaN based LEDs can emit light from ultraviolet to green light. It is possible to produce a wide range of light emitting diodes if the UV or blue light emitting diode is combined with fluorescent material. A fluorescent substance is a luminescent substance that converts the absorbed light into light radiation at different wavelengths

epitaxial growth

The invention relates to a technique for forming a semiconductor layer. The crystal layer formed on the substrate is the same as the substrate.

Source: Electronic Engineering album