摘要:

It is of great interest to establish the relationship between the conductivity and the concentration of dopants in ice, as in semiconductors in general. In a widely employed technique, the electrodes are placed perpendicular to the direction of sample growth, which is also the direction of the concentration gradient invariably present. This arrangement is called a resistance measurement. In the improved technique, the electrodes are placed parallel to the concentration gradient; this arrangement is called a conductance measurement. The error in estimation of the bulk conductivity resulting from these distinct methods of measurement is computed, using as the reference, the conductivity associated with the average concentration. Three types of dopant concentration gradients are dealt with: the Pfann, the exponential, and the linear. In addition, the cases where the conductivity is proportional to the first power and to the square root of the concentration are considered. It is found that the improved technique always leads to a smaller error than the usual one, other factors being equal. Furthermore, the techniques recommended for improving doping uniformity (stirring of solution during freezing and freezing only a portion of the sample) are shown to have a sound theoretical basis. The partition coefficient of HCl between ice and water has been calculated based on the Pfann equation and measurement of the average concentration of HCl in doped ice and the known initial solution concentrations.kis of the order of 0.01.

ISSN:0021-8979    

DOI:10.1063/1.1657986

出版商:AIP    

年代:1969

数据来源: AIP

摘要:

Mass spectrometric measurements have been made of the ions present in rf discharges of argon and argon containing small concentrations of cesium. Data were obtained for normalized argon and cesium pressures up to 3 and 4×10−3Torr, respectively. The relative ion singals are functions not only of the argon and cesium concentrations but also of the plasma excitation power. For argon‐cesium mixtures the primary ions that are observed are Ar+, Ar2+, and Cs+. Analysis of the data for Ar+and Ar2+suggests that Ar2+is produced by both Hornbeck‐Molnar and three‐body conversion processes. Interpretation of the results leads to the conclusion that in the present study Cs+is formed by both direct ionization and by collisions of argon metastables with neutral cesium.

ISSN:0021-8979    

DOI:10.1063/1.1657987

出版商:AIP    

年代:1969

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1657988

出版商:AIP    

年代:1969

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1657989

出版商:AIP    

年代:1969

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1657990

出版商:AIP    

年代:1969

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1657991

出版商:AIP    

年代:1969

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1657992

出版商:AIP    

年代:1969

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1657993

出版商:AIP    

年代:1969

数据来源: AIP