Exciton absorption of light in laminated semiconductor wafers

The exciton absorption of light in samples composed of semiconductor wafers is analyzed, assuming a resonance mechanism of exciton migration from one wafer to another and weak interaction among the wafers. Expressions for the absorption coefficient are derived, assuming that absorption is caused by excitation of surface exciton states. For 'shallow' surface states, absorption is found to be comparable to bulk absorption. The shape of the absorption line resulting from the wafer thickness distribution is identified.