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THE BELL SYSTEM TECHNICAL JOURNAL, MAY 1953 



Fig. 1 — Assumed distribution of excess of donor concentration over acceptor 

 concentration. 



centration of mobile electrons — or of holes — in intrinsic material at 

 the given temperature.) 



The set of equations which (together with boundary conditions to be 

 specified later) determines the electric field in the intrinsic region < 

 y < Lis: 



dE a , 



n), 



dy kT '^ ixJtT ' 



— = -±nF -t- ^'" 

 dy kT "^ ^,„kT ' 



Ty--^' 



^ = 9(!/ - r), 

 du 



dy 



= -qig - r), 



Inhere E: electric field intensity, volts/m. 



q : electronic charge magnitude, coulombs. 



K : absolute dielectric constant, farads/m. 



p : hole concentration, m~'. 



n : electron concentration, m~'^ 



k :Boltzmann'8 constant, joules/°K. 



(1) 



(2) 

 (3) 

 (4) 

 (5) 

 (6) 



