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We have studied the light emission from CsI and NH4Cl films that were bombarded simultaneously with H−, low mass organic, and (CsI)nI− (n = 0–2) ions in the keV energy range (25–45 keV) at room temperature. Photons were detected from the impact of individual primary ions with a single photon counting photomultiplier, and were analyzed using time resolved and wavelength analysis. For CsI, fast (τ ≤ 12 ns) and slow (τ ≥ 650 ns) component decays were observed for all projectiles used. The fast component's emission was ∼ 300 nm while the slow component's emission was in the visible. Only a fast component (τ < 3 ns) was observed in the UV region for NH4Cl. Our data suggest that the light emission from both samples is due to the radiative relaxation of self-trapped excitons which are produced by electronic interactions between the primary ions and the target atoms.

We have observed the light emission from CsI films, at room temperature, induced by single ${\mathrm{H}}^{\mathrm{\ensuremath{-}}}$, low-mass organic, and CsI negative ions in the 20--45-keV energy range. The light signal was studied using wavelength and time-resolved analysis in order to probe the energy-transfer process between keV ions and target atoms. Prompt-decay photon yields are found to be proportional to the energy deposited into the electronic system of the target directly through electronic stopping and indirectly via the collision cascade. Photons are attributed to the luminescence of self-trapped excitons. Solid-state luminescence may be useful in probing the interactions between projectile and target in the time interval between the impact and the sputtering of surface species.

We describe an ion source based on the spontaneous desorption process. The production, acceleration, and separation processes allow for the production of keV energy polyatomic ions while maintaining a high signal‐to‐background ratio. Both atomic and polyatomic ions with up to 37 keV energy were generated. Because the spontaneous desorption process is naturally pulsed, the ion source was attached to a dual time‐of‐flight mass spectrometer for secondary ion mass spectrometry experiments. In this article, we describe the design of both the polyatomic ion source and the mass spectrometer.