摘要:

Single‐crystal multilayers of the dilute magnetic semiconductor Cd1−xMnxTe alternating with CdTe have been successfully grown for the first time by MBE. Experimental techniques used to prepare the various superlattice samples are described. Results of x‐ray diffraction and photoluminescence film characterization experiments are also discussed.

ISSN:1071-1023    

DOI:10.1116/1.583121

出版商:American Vacuum Society    

年代:1985

数据来源: AIP

摘要:

In this paper we report the growth of Cd1−xMnxTe superlattices (varyingx) on GaAs substrates. Transmission electron microscopy of thinned specimens clearly show layers of uniform composition with abrupt interfaces; the lattice mismatch (≂0.6%) between superlattice layers is accomodated by elastic strain rather than misfit dislocation networks. The superlattices consistently show orders of magnitude greater photoluminescence (PL) intensity compared to thin films and bulk samples; in fact, the PL intensity is somewhat larger than that obtained from state of the art (Ga, Al) As double heterostructures under identical conditions of excitation. Removal of the substrate by etching produces a shift in the PL peak as well as a reduction in the spectral width indicating that the presence of the substrate causes inhomogeneous broadening due to nonuniform strains.

ISSN:1071-1023    

DOI:10.1116/1.583122

出版商:American Vacuum Society    

年代:1985

数据来源: AIP

摘要:

The first epitaxial growth of a hexagonal structure lanthanide trifluoride on a semiconductor is reported: LaF3on Si (111). LEED, RHEED, and x‐ray diffraction studies show that thec‐axis of LaF3is normal to the Si(111) plane. A similar epitaxial relation is expected for other members of the lanthanide trifluoride family: CeF3, PrF3, and NdF3which are isomorphous with LaF3and have a closer (basal plane) lattice parameter match to Si(111). The hard, water insoluble nature of these materials makes them more practicable than group II fluorides as exploratory films for semiconductor passivation, gate insulator, and epitaxial interlayers.

ISSN:1071-1023    

DOI:10.1116/1.583124

出版商:American Vacuum Society    

年代:1985

数据来源: AIP

ISSN:1071-1023    

DOI:10.1116/1.583125

出版商:American Vacuum Society    

年代:1985

数据来源: AIP

摘要:

Many works are now conducted in the worldwide scale on silicon molecular beam epitaxy (Si MBE) including homoepitaxy, doping, heteroepitaxy such as silicon/insulator, silicon/other semiconductor, and silicon/metal (silicide), and poly‐Si deposition. As for device applications, work is now moving from conventional discrete devices to integrated circuits and structures unique to Si MBE. In this paper, various aspects of Si MBE are reviewed.

ISSN:1071-1023    

DOI:10.1116/1.583126

出版商:American Vacuum Society    

年代:1985

数据来源: AIP

ISSN:1071-1023    

DOI:10.1116/1.583127

出版商:American Vacuum Society    

年代:1985

数据来源: AIP

摘要:

The defect structure of Si MBE layers grown on porous silicon substrates depends critically on the technique for cleaning the substrate surface. Cross‐sectional TEM studies demonstrate that a combined sputter‐clean and thermal cycle markedly reduces the density of microtwins and dislocations in the epitaxial layer when compared with simple thermal cleaning. X‐ray diffraction studies show the porous silicon layer to be lattice‐matched to the underlying (100) bulk silicon substrate in the plane of the wafer so that misfit dislocations are not expected in the epitaxial layer. However, both the lattice parameter of the porous layer in the direction normal to the wafer and the thermal stability of the porous layer in vacuum, depend upon the resistivity of the starting wafer. The photoluminescence of a 4‐μm MBE layer grown on a sputter‐cleaned, high resistivity substrate is still dominated by recombination at dislocations.

ISSN:1071-1023    

DOI:10.1116/1.583128

出版商:American Vacuum Society    

年代:1985

数据来源: AIP

摘要:

Epitaxial Si/CaF2/Si(111) structures have been grown by molecular beam epitaxy. Planar and cross‐sectional transmission electron microscopy has been used for characterization of these structures. The CaF2layer is high quality, single crystal material exhibiting type B epitaxy with respect to the Si substrate. On the other hand, the Si overgrowth layer consists of a mixture of crystallites which are aligned either with the Si substrate or with the CaF2. The defect density in the overgrown Si improves with distance from the interface with the CaF2. Variation of the substrate temperature during growth has relatively little effect on the quality of the epitaxial Si.

ISSN:1071-1023    

DOI:10.1116/1.583129

出版商:American Vacuum Society    

年代:1985

数据来源: AIP

ISSN:1071-1023    

DOI:10.1116/1.583130

出版商:American Vacuum Society    

年代:1985

数据来源: AIP

ISSN:1071-1023    

DOI:10.1116/1.583131

出版商:American Vacuum Society    

年代:1985

数据来源: AIP