摘要:

A floating zone refining apparatus for silicon, which can operate unattended, has been assembled to assist in the production of high purity material for research purposes. Features of this equipment are a simple mechanical drive, a switching panel to recycle the apparatus, and a self‐stabilizing rf heating circuit to maintain constant zone length. Silicon containing less than 1 part per billion of electrically active impurities (resistivity of 16 000 ohm cm and lifetime of 1.2 milliseconds) has been prepared. The effect of many‐pass refinings on the diameter of the sample is discussed. Surface tension effects on material transport are significant.

ISSN:0034-6748    

DOI:10.1063/1.1715905

出版商:AIP    

年代:1957

数据来源: AIP

摘要:

Pirani gauges are used in an ac bridge circuit to sense deviation from the set point, and with the aid of a porportional leak valve, control the pressure of laboratory‐scale vacuum systems over the range of 0.1 to 10 000 &mgr; of Hg. Pressure fluctuations from the controller action are negligible and stability of ±1% has been obtained over long periods without operator attention. Set point is easily adjustable by panel control knob. Commercial components are used except for the leak valve which is of special construction.

ISSN:0034-6748    

DOI:10.1063/1.1715906

出版商:AIP    

年代:1957

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1715908

出版商:AIP    

年代:1957

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1715909

出版商:AIP    

年代:1957

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1715910

出版商:AIP    

年代:1957

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1715911

出版商:AIP    

年代:1957

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1715913

出版商:AIP    

年代:1957

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1715914

出版商:AIP    

年代:1957

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1715915

出版商:AIP    

年代:1957

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1715916

出版商:AIP    

年代:1957

数据来源: AIP