- Email: [email protected]
ITS and optilas for Wyko
Soviet quartz coatings
Epiquip antimony MOCVD project
The L e n i n g r a d S t a t e T e c h nical University is working
on chemically reliable coating designed to eliminate contact and interaction of aggressive melts and gaseous fluids with technological fitting made of quartz and glass. The coating consists of the rare-earth oxide (REO). Being both safe and ecologically clean the methods of the coating application do not need any extraordinary equipment. Resulting from annealing the formed intermediate layer of complex chemical compound-RE ortho- or metasilicate- provides for excellent adhesion of the coating to quartz and glass. The similar values of the expansion coefficient of REO and quartz develop the protective functions of the coating operating in high temperature ranges up to 1200-1300°C, while the process of quartz devitrification becomes slower. With the help of standard vacuum equipment it is possible to lay the coating upon quartz crucibles of up to 330 mm diameter, also boats, long tubes, barrels and other manufactured articles for the semiconductor, chemical and medicine industry. The protective coatings may be utilized in all aspects of semiconductor manufacture, e.g. growing crystals and epitaxy as well as when dealing with aggressive melts, and for technology of HTSCs. The similar boron nitride products, conventionally applied in semiconductor technology, cost several times as much. High purity of grown semiconductor crystals and layers and the unique possibility to apply chemically active doping im-
GaAs:Sb EL2
u~
I
15(] 200
I 250
I 300
I 350
400
Temperature (K)
A typical spectrumfor the Sb-doped samples. Two different electron traps be seen in this spectrum, whereasin undoped referencesamples only the high-temperature level is seen
can
A project on MOCVD growth using trimethylantimony (TMSb) demonstrates the flexible design of the Epiquip VP502-RP MOCVD reactor which allows the growth of antimony-containing compounds, even though they are known to cause problems due to pre-reactions and depositions in the exhaust system. The project was concerned with the growth of Sb-doped GaAs and the characterization of defects associated with the hetero-antisite defect, Sboa. The influence of this defect on the EL2 level was also studied. In the second project, GaSb was grown and electrically characterized. GaSb, with a band gap corresponding to a wavelength of 1.6 lam, is a potential material for long wavelength optoelectronic components. GaAs doped with antimony was grown at atmospheric pressure at a growth temperature of 680°C in a conventional Epiquip VP502-RP reactor. The precursors were TMGa, TMSb and ASH3. Details of the growth conditions can be found in Yakimova et al. (1991). The samples were low n-type with concentrations of S up to 5.10~8cm-3, depending on the mole fraction of TMSb used during growth. The Sb concentration was determined using SIMS, PIXE and analysis of XRDCR curves. The layers were used to make Schottky diodes and these were characterized by DLTS. The diagram shows a typical spectrum for one of the Sb-doped samples. • Contact: Epiquip AB, S-223 70 Lund, Sweden. Tel~fax: [46] ( 0 ) 4 6 1 6 8 7 4 0 / 148234.
purities are guaranteed. • Contact: Leningrad State Technical University, Experimental Physics Dept., R&D Laboratory of
Semiconductors Technology, Polytechnicheskaya Str. 29, Leningrad, 195251, USSR. Tel~fax: [7] (812) 5527817 / 2920094.
~i~i~i~i~i~i~i~i~!~i~i~i~i~i~!~i~!~!~i~i~i!~i~!~i~i~i~!~:~ !~'~i :ii/~i:i~i::::!:i:i:%~ii~i~i:i:i~i~i~~i i~!i:i~i:i:iJ:~ i;,i:!~i:~i:i~i~i~i:~i~i,i~!,~,~i~i~!,!i+~i~i,~i
ITS and Optilas for Wyko Intertrade Scientific (ITS) will represent the Wyko line of non-contact surface profilers and atomic force microscope products throughout Europe. The Optilas Group will represent the Wyko line of interferometry products throughout Europe. AG Electro-Optics Ltd will continue to represent Wyko in the UK, the Irish Republic, and Scandinavia, and Elicam will continue to serve Italy. • Contact: WYKO Corp., 2650 E. Elvira Road, Tucson, A Z 85706, USA. Tel~ fax: (602) 741 1 0 4 4 / 1799.
Logitech polish The PS2000 is for high quality flat polishing using both synthetic plates and traditional pitch. It provides a new level of automated control over specimen flatness, to tenth wave precision (HeNe), using custom designed electronics. Developed to produce flatness of X/10 on samples up to 100mm (4in) in diameter, the PS2000 is nevertheless easy to use by both inexperienced and experienced operators. Process times are significantly reduced in comparison with traditional technology because wear conditioning is virtually eliminated. The plate shape can be altered simply at the touch of a button. • Contact: Logitech Ltd, Erskine Ferry Road, Old Kilpatrick, Glasgow, G60 5EU, Scotland, UK. Tel~ fax: [44] ( 0 ) 3 8 9 75444 / 79042.
Epiquip antimony MOCVD project
The L e n i n g r a d S t a t e T e c h nical University is working
on chemically reliable coating designed to eliminate contact and interaction of aggressive melts and gaseous fluids with technological fitting made of quartz and glass. The coating consists of the rare-earth oxide (REO). Being both safe and ecologically clean the methods of the coating application do not need any extraordinary equipment. Resulting from annealing the formed intermediate layer of complex chemical compound-RE ortho- or metasilicate- provides for excellent adhesion of the coating to quartz and glass. The similar values of the expansion coefficient of REO and quartz develop the protective functions of the coating operating in high temperature ranges up to 1200-1300°C, while the process of quartz devitrification becomes slower. With the help of standard vacuum equipment it is possible to lay the coating upon quartz crucibles of up to 330 mm diameter, also boats, long tubes, barrels and other manufactured articles for the semiconductor, chemical and medicine industry. The protective coatings may be utilized in all aspects of semiconductor manufacture, e.g. growing crystals and epitaxy as well as when dealing with aggressive melts, and for technology of HTSCs. The similar boron nitride products, conventionally applied in semiconductor technology, cost several times as much. High purity of grown semiconductor crystals and layers and the unique possibility to apply chemically active doping im-
GaAs:Sb EL2
u~
I
15(] 200
I 250
I 300
I 350
400
Temperature (K)
A typical spectrumfor the Sb-doped samples. Two different electron traps be seen in this spectrum, whereasin undoped referencesamples only the high-temperature level is seen
can
A project on MOCVD growth using trimethylantimony (TMSb) demonstrates the flexible design of the Epiquip VP502-RP MOCVD reactor which allows the growth of antimony-containing compounds, even though they are known to cause problems due to pre-reactions and depositions in the exhaust system. The project was concerned with the growth of Sb-doped GaAs and the characterization of defects associated with the hetero-antisite defect, Sboa. The influence of this defect on the EL2 level was also studied. In the second project, GaSb was grown and electrically characterized. GaSb, with a band gap corresponding to a wavelength of 1.6 lam, is a potential material for long wavelength optoelectronic components. GaAs doped with antimony was grown at atmospheric pressure at a growth temperature of 680°C in a conventional Epiquip VP502-RP reactor. The precursors were TMGa, TMSb and ASH3. Details of the growth conditions can be found in Yakimova et al. (1991). The samples were low n-type with concentrations of S up to 5.10~8cm-3, depending on the mole fraction of TMSb used during growth. The Sb concentration was determined using SIMS, PIXE and analysis of XRDCR curves. The layers were used to make Schottky diodes and these were characterized by DLTS. The diagram shows a typical spectrum for one of the Sb-doped samples. • Contact: Epiquip AB, S-223 70 Lund, Sweden. Tel~fax: [46] ( 0 ) 4 6 1 6 8 7 4 0 / 148234.
purities are guaranteed. • Contact: Leningrad State Technical University, Experimental Physics Dept., R&D Laboratory of
Semiconductors Technology, Polytechnicheskaya Str. 29, Leningrad, 195251, USSR. Tel~fax: [7] (812) 5527817 / 2920094.
~i~i~i~i~i~i~i~i~!~i~i~i~i~i~!~i~!~!~i~i~i!~i~!~i~i~i~!~:~ !~'~i :ii/~i:i~i::::!:i:i:%~ii~i~i:i:i~i~i~~i i~!i:i~i:i:iJ:~ i;,i:!~i:~i:i~i~i~i:~i~i,i~!,~,~i~i~!,!i+~i~i,~i
ITS and Optilas for Wyko Intertrade Scientific (ITS) will represent the Wyko line of non-contact surface profilers and atomic force microscope products throughout Europe. The Optilas Group will represent the Wyko line of interferometry products throughout Europe. AG Electro-Optics Ltd will continue to represent Wyko in the UK, the Irish Republic, and Scandinavia, and Elicam will continue to serve Italy. • Contact: WYKO Corp., 2650 E. Elvira Road, Tucson, A Z 85706, USA. Tel~ fax: (602) 741 1 0 4 4 / 1799.
Logitech polish The PS2000 is for high quality flat polishing using both synthetic plates and traditional pitch. It provides a new level of automated control over specimen flatness, to tenth wave precision (HeNe), using custom designed electronics. Developed to produce flatness of X/10 on samples up to 100mm (4in) in diameter, the PS2000 is nevertheless easy to use by both inexperienced and experienced operators. Process times are significantly reduced in comparison with traditional technology because wear conditioning is virtually eliminated. The plate shape can be altered simply at the touch of a button. • Contact: Logitech Ltd, Erskine Ferry Road, Old Kilpatrick, Glasgow, G60 5EU, Scotland, UK. Tel~ fax: [44] ( 0 ) 3 8 9 75444 / 79042.