Photonic devices formed of high-purity molybdenum oxide

Abstract

The present invention is directed to photonic devices which emit or absorb light with a wavelength shorter than that GaN photonic devices can emit or absorb. The devices according to the present invention are formed using molybdenum oxide of a high purity as a light emitting region or a light absorbing region. New inexpensive photonic devices which emit light with a wavelength from blue to deep ultraviolet rays are realized. The devices according to the present invention can be formed at a temperature relating low such as 700° C.

1 . A semiconductor photo-device wherein molybdenum oxide is used in at least one layer which converts electrical energy to light or light to electrical energy. 
     
     
         2 . The semiconductor photo-device according to  claim 1 , wherein said at least one layer comprises at least a part of a light-emitting or light-absorbing region in a photo-conductive device, and said light-emitting or light-absorbing region composes at least a part of a photo-conductive device, a photo-diode, a photo-transistor, a light-emitting diode, a semiconductor laser, a solar cell or a CCD. 
     
     
         3 . The semiconductor photo-device according to  claim 1 , wherein said molybdenum oxide has a high purity property so that efficient conversion from electrical energy to light or from light to electrical energy occurs in said molybdenum oxide region. 
     
     
         4 . The semiconductor photo-device according to  claim 1 , wherein said molybdenum oxide is a high purity molybdenum oxide which is formed by vapor phase deposition at a temperature lower than 700° C. 
     
     
         5 . The semiconductor photo-device according to  claim 1 , wherein said molybdenum oxide is crystalline having a high purity and has a bandgap of 3.45-3.85 eV. 
     
     
         6 . A light emitting diode comprising: a layer of molybdenum oxide on a substrate; a layer of n-type molybdenum oxide; and a layer of p-type molybdenum oxide so that said layer of n-type molybdenum oxide and said layer of p-type molybdenum oxide forms a pn junction from which light is emitted. 
     
     
         7 . A light emitting diode comprising: a layer of molybdenum oxide on a substrate; a buffer layer of molybdenum oxide on said molybdenum oxide layer; a layer of n-type molybdenum oxide on said buffer layer; and a layer of p-type molybdenum oxide on said n-type layer. 
     
     
         8 . Laser diodes comprising a layer of molybdenum oxide on a substrate; a first cladding layer of n-type semiconductor on said molybdenum oxide layer, said first cladding layer having a bandgap larger than that of said molybdenum oxide; an active layer of p-type molybdenum oxide on said first cladding layer; and a second cladding layer of p-type semiconductor on said active layer, said second cladding layer having a bandgap larger than that of said molybdenum oxide. 
     
     
         9 . A laser diode comprising: a layer of molybdenum oxide on a substrate; a buffer layer of molybdenum oxide on said layer; a first cladding layer of n-type semiconductor on said buffer layer, said first cladding layer having a bandgap larger than that of said molybdenum oxide; an active layer of p-type molybdenum oxide on said first cladding layer; and a second cladding layer of p-type semiconductor on said active layer, said second cladding layer having a bandgap larger than that of said molybdenum oxide. 
     
     
         10 . The light emitting diode according to  claim 6 , wherein said substrate is composed of molybdenum. 
     
     
         11 . The laser diode according to  claim 8 , wherein said substrate is composed of molybdenum. 
     
     
         12 . The laser diode according to  claim 8 , wherein said first and second cladding layers are composed of chromium molybdenum oxide. 
     
     
         13 . The light emitting diode according to  claim 7 , wherein said substrate is composed of molybdenum. 
     
     
         14 . The laser diode according to  claim 9 , wherein said substrate is composed of molybdenum. 
     
     
         15 . The laser diode according to  claim 9 , wherein said first and second cladding layers are composed of chromium molybdenum oxide. 
     
     
         16 . The laser diode according to  claim 11 , wherein said first and second cladding layers are composed of chromium molybdenum oxide. 
     
     
         17 . The laser diode according to  claim 14 , wherein said first and second cladding layers are composed of chromium molybdenum oxide.