Resistance of Thin Metallic Films. 



481 



of the exponential functions occurring in (10) are such as to 

 retain the sharpness of the bend in the curve for s 1 plotted 



Esr. 4. 

















The ordi nates of tkt cwrve represent 6, 







ie. Lhe ratio ot [tit LIlcoreUcaL speciiic. 

 resistance to lhe normal sptciHcrtsista.net 

 or tkt metal in hulk at tkt same temperature. 























































1 











V 

























' 



; 



5 + 



Vataes of (kmuS) = 



4-«g 



against t, even though ?r may be made to vary very slowly 

 with t. Apart from this, however, we should not expect a 

 slow variation of il 2 with t in the neighbourhood of the bend. 

 L c. under the conditions in which the looseness of the 

 packing is pronounced. 



The variations of the resistances of the films with temperature. 

 An examination of Tables II. and III. will show : 



(1) that for thick films, e. g. Table III. films 4-10, also 

 Table II. films 6 and 7, the specific resistance increases 

 slightly with rise in temperature. 



(2) For thin films, e. g. Table II. films 1-4, s decreases 

 rapidly with rise in temperature. 



(^3) In the case of intermediate films, such as film 5, 

 Table II. and film 3, Table III., the temperature coefficient 

 shows a reversal of sign over the range of temperature 

 employed. 



The fact that the temperature coefficient is of opposite 

 sign for thick films to what it is for thin films is already 

 known, but as far as I know, the reversal of the temperature 

 coefficient with alteration of temperature in the same film 

 has not been recorded. The explanation of these curious 



Phil. Mag. S. 6. Vol. 28. No. 166. Oct. 1914. 2 I 



