ISSN:
1077-3118
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Remarkable reduction of contact resistance in the metal-p+ silicon Schottky barriers is obtained using the BF2/B mixed implant instead of the BF2 implant. Upon the annealing, higher remaining contents of both boron and fluorine in a shallow p+ surface layer are observed in the mixed implanted silicon. Variation of the dopants loss observed with different F doses is explained by introducing the following two types of surface reaction, i.e., (1) recombination of F–Si to make gaseous fluorosilyl/oxyfluorosilyl products and (2) recombination of F–B to form gaseous boron fluorides. Increasing the amount of the F–B reaction accelerates the recombination reaction of F–Si due to the reduced surface p+ doping level, and then results in the anomalous enhancement of the F removal. For the mixed implant, shortening of the average interdopant separation due to higher B contents within the contact depletion width reduces the potential fluctuations induced by the dopant discreteness, and thus leads to the improved uniformity of contact resistance. © 1999 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.124669
