ZnMgSSe and Related Hetero-structures Grown by Metalorganic Chemical Vapor Deposition

We have succeeded in epitaxial growth of ZnMgSSe by an atmospheric pressure metalorganic chemical vapor depos玉tion(MOCVD)using dimethylzinc(DMZll)，bis一 (methylcyclopentadienyl)magnesium((MeCp)2Mg)，diethylsulfide(DES)and dimethylselenium(DMSe)．The Mgcomposition is achieved up to13％with mirror-1ike surface morphology，Photoluminescence spectrumat42K and X-ray rockingcllrve ind玉c＆te the excellent quality of ZnMgSSe la七tice-matched to GaAs．Using ZnSe／ZnMgSSe double heterostructure，we have achieved photo-pumped lasing action with a peak wavelength of465nm and a threshold excitation power of70kW／cm2at room temperature，An intemal loss of4．6cm-I is estimated from the cavity length dependence．The low intemal loss，being coml)arable to that of a molecular beam epitaxy(MBE)一grown DH，shows a feasibilityofMOCVD-grownDHdevice， 1 1NTRODUCTlONThe ZnMgSSe system is suitable to fabricate the cladding layer of blue enlitting laser diodes (LDs)，since iもhas a larger energy band-gap and a smaller refractive index than ZnSSe1-4)， promising good optical and carrier confinement in a ZnSSe／ZnMgSSe double he七erostructure(DH)． The band-gap energy is variable from2，8eV to about4．5eV by cQntrolling the Mg contents．The fh・st ZnMgSSe quatemary compound system was grown by molecular beam epitaxy(MBE)1)． Pulsed photopumped blue Iasing was observed at high temperatures llp to500K5，6)，Recently， roomtemperaturecontinuous-waveoperationin the blue-green region of the spectrum was also achieved by the MBE-grown ZnMgSSe injection lasers7-9)．