The minority carrier lifetime is a measure of how long a carrier is likely to stay around for before recombining. It is often just referred to as the "lifetime" and has nothing to do with the stability of the material. Stating that "a silicon wafer has a long lifetime" usually means minority carriers generated in the bulk of the wafer by light or other means will persist for a long lifetime before recombining. Depending on the structure, solar cells made from wafers with long minority carrier lifetimes will usually be more efficient than cells made from wafers with short minority carrier lifetimes. The terms "long lifetime" and "high lifetime" are used interchangably.

The low level injected material (where the number of minority carriers is less than the doping) the lifetime is related to the recombination rate by:

,

where τ is the minority carrier lifetime, Δn is the excess minority carriers concentration and R is the recombinaton rate.

The auger lifetime is a function of the carrrier concentration and is given by:

Where the auger coefficienct C is typically given as: 1.66 × 10^-30cm⁶/s (Sinton, Altermatt)