Sapphire wafer with complete orientation options including C plane , A plane , R plane and M plane , in diameter range  from 1" to 4" , square substrate is also available as well , size from 10 x 10 mm to 100 x 100 mm . Substrate are produed as per SEMI standards it has good surface finish Ra < 5A and high cleanliness , SWI can offer epi ready grade sapphire wafer for your epitaxial growth . Sapphire wafer are produced by Czochralski method , due to it's high strength, high anti-corrosion high anti-abrasion , low dielectric loss and good electrical insulation , single crystal  sapphire wafer plays an increasingly important role as a material for blue LED and high Tc superconductor and microwave applications. Contact us for for further information on price & delivery time .

Thick GaN layers were grown by hydride vapor phase epitaxy (HVPE) with the aim of using these layers as a homoepitaxial substrate to improve device quality of laser diodes or light emitting diodes. HVPE is very useful for thick layer growth since the growth rate can reach from several ten up to one hundred micron per hour. In this experiment, the growth began as selective growth through openings formed in a SiO2 mask. Facets consisting of planes were formed in the early stage and a continuous film developed from the coalescence of these facets on the SiO2 mask. As a result, GaN layers with a dislocation density as low as 6×107 cm^-2 were grown on 2-inch-diameter sapphire wafers. These GaN layers were crack-free and had mirror-like surface.


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Kinetics of Al2O3 surface nitridation and subsequent growth of AlN films on the sapphire substrate by ammonia molecular beam epitaxy (MBE) are investigated. Surface morphology evolution during AlN growth is studied in situ by reflection high energy electron diffraction and ex situ by atomic force microscopy. It is found that the surfaces of AlN layers thicker than 100 nm have two major features: a quite smooth background and noticeable amount of hillocks. The influence of growth conditions on the AlN surface morphology is studied in order to find a way for reducing of the hillocks density. A modification of nitridated sapphire surface by small amount of Al (1–2 monolayers) with subsequent treatment of the surface under ammonia flux is proposed. An improvement of AlN surface morphology of the layers grown on the modified surfaces is demonstrated.

Single‐crystal layers of AlN have been grown on sapphire substrates between 1000 and 1100 °C by vapor‐phase reaction of aluminum chlorides with ammonia. The purity, color, crystallinity, growth morphology, and electrical resistivity of the epitaxial layers have been investigated. Infrared specular reflection measurements showed the presence of an appreciable strain at the AlN‐sapphire epitaxy interface. Optical absorption data strongly suggest the AlN is a direct band‐gap material with a value of about 6.2 eV at room temperature.


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Sapphire is a material of a unique combination of physical, chemical and optical properties, which make it resistant to high temperature, thermal shock, water and sand erosion, and scratching. It is a superior window material for many IR applications from 3µm to 5µm. C-plane sapphire substrates are widely used to grow III-V and II-VI compounds such as GaN for blue LED and laser diodes, while R-plane sapphire substrates are used for the hetero-epitaxial deposition of silicon for microelectronic IC applications.

We report high-throughput growth of highly aligned single-walled carbon nanotube arrays on a-plane and r-plane sapphire substrates. This is achieved using chemical vapor deposition with ferritin as the catalyst. The nanotubes are aligned normal to the direction for growth on the a-plane sapphire. They are typically tens of micrometers long, with a narrow diameter distribution of 1.34 ± 0.30 nm. In contrast, no orientation was achieved for growth on the c-plane and m-plane sapphire, or when Fe films, instead of ferritin, were used as the catalyst. Such orientation control is likely related to the interaction between carbon nanotubes and the sapphire substrate, which is supported by the observation that when a second layer of nanotubes was grown, they followed the gas flow direction. These aligned nanotube arrays may enable the construction of integrable and scalable nanotube devices and systems.


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GaN micro-light-emitting diodes (micro-LEDs) with monolithically integrated microlenses have been demonstrated. Microlenses, with a focal length of 44 μm and a root mean square roughness of ∼1 nm, have been fabricated on the polished back surface of a sapphire substrate of an array of micro-LEDs by resist thermal reflow and plasma etching. The optical properties of the microlenses have been demonstrated to alter the emission pattern of the LED emitters. The cone of light emitted from this hybrid device is significantly less divergent than a conventional broad-area device. This combination of micro-LED and microlens technologies offers the potential for further improvement in the overall efficiency of GaN-based light emitters.

The fabrication and characterization of a metal semiconductorfield effect transistor (MESFET) based on single crystal GaN. The GaN layer was deposited over sapphire substrate using low pressuremetalorganic chemical vapor deposition. MESFET devices were fabricated on isolated mesas using TiAu for the source and drain ohmic contacts and silver for the gate Schottky. For devices with a gate length of 4 μm (channel opening, i.e., source to drain separation of 10 μm), a transconductance of 23 mS/mm was obtained at −1 V gate bias. Complete pinch‐off was observed for a gate potential of −12 V.


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