TABLE OF CONTENTS (Edited By K. Jones)
D. de Cogan and Y.M. Haddara (Updated by K. Jones)
October 1998
This Datareview presents data on the diffusion behaviour of the acceptors Al, Ga, In and Tl in crystalline silicon. A range of impurity sources and diffusion conditions have been employed for each of the impurities considered. Sequential diffusions of acceptor and donor impurities are also described. Both silicon oxide and nitride have been used as mask materials during diffusion processes and the advantages/disadvantages of each are outlined
The interest in aluminium as an impurity arises from the fact that it diffuses faster than other acceptors. The solubility limit is, in most cases, low, which reduces dislocation formation and there is no evidence of intermetallic reactions with the host element.
The diffusion properties can be characterised by either monitoring junction depth (using a bevel and stain technique) or by means of a complete profile determination. The standard method which was used by Fuller and Ditzenberger [B1] consists of measuring sheet resistance again. Other techniques, such as Hall effect and spreading resistance, are sometimes used.
The early studies of aluminium diffusion were the subject of much controversy. Values of diffusion constant differed by up to two orders of magnitude. TABLE B1 provides data on the pre-exponential and activation terms in D = D 0 exp(-E/kT) quoted by different authors. The diffusion constant at 1200 C is given for...
