The motion of lithium in ann‐pjunction under reverse bias is discussed. Expressions are derived for the distribution of lithium in the ``intrinsic'' layer as it depends on time. Results for the width of this layer agree with the earlier calculations of Pell. Information concerning this width simplifies the calculation of the detailed distribution. Thus it is convenient to combine Pell's method with ours to supply an expeditious method for arriving at the distribution. The results of the calculation indicate that the so‐called ``intrinsic'' layer produced by drift under reverse bias should beveryhighly compensated over most of its extent.