Monolithic Semiconductor

PRP has been designing and processing monolithic LED arrays since the company formed in 1989.

So what is a monolithic LED…

A monolithic LED differs from a standard LED in that it is a single piece of semiconductor where the light emitting active regions have been defined within it.  This allows for emitters to be custom shapes and sizes and if required to be spaced so as to achieve very high resolutions.  Wavelengths across the visible spectrum and into the UV and IR are available.

Individual emitters can be less than 10 microns with gaps of just a few microns, luminance values of greater than 35000 cdm^-2 are achievable for visible wavelengths.

How can they be used…

Using their extensive in-house design and development experience PRP can package its innovative Micro-Display technology into a single monolithic chip customised to meet a customer’s exact specifications. PRP’s monolithic LEDs are processed using a variety of techniques and are produced in the same way as an IC on a complete epitaxial wafer, this means the area of the material used is relatively small allowing for good uniformity of emission and wavelength across the array.

Depending on the application monolithic LEDs can be assembled into a variety of packages and driven by off the shelf or custom LED drivers, integration with optics is also easily achievable.

Applications for this kind of chip include, but are not limited to, reticule displays in optical systems, gunsights and printing, see examples below:

• A rangefinder that includes a high reliability, high dynamic range but low power information display comprising of several 14 segment chips and an aiming mark coupled into custom optics.
• A large format commercial printing application where each printhead writer has 17280 individually addressable emitters with a 21.15 micron pitch (1200dpi).

PRP Optoelectronics’ in-house fabrication produce optoelectronic devices in compound semiconductor and semiconductor alloy materials.