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The development of a new radiation effects microscopy (REM) technique is crucial as emerging semiconductor technologies demonstrate smaller feature sizes and thicker back end of line (BEOL) layers. To penetrate these materials and still deposit sufficient energy into the device to induce single event effects, high energy heavy ions are required. Ion photon emission microscopy (IPEM) is a technique that utilizes coincident photons, which are emitted from the location of each ion impact to map out regions of radiation sensitivity in integrated circuits and devices, circumventing the obstacle of focusing high-energy heavy ions. Several versions of the IPEM have been developed and implemented at Sandia National Laboratories (SNL). One such instrument has been utilized on the microbeam line of the 6 MV tandem accelerator at SNL. Another IPEM was designed for ex-vacu use at the 88″ cyclotron at Lawrence Berkeley National Laboratory (LBNL). Extensive engineering is involved in the development of these IPEM systems, including resolving issues with electronics, event timing, optics, phosphor selection, and mechanics. The various versions of the IPEM and the obstacles, as well as benefits associated with each will be presented. In addition, the current stage of IPEM development as a user instrument will be discussed in the context of recent results. [ABSTRACT FROM AUTHOR]

To investigate the effects of gamma-ray irradiation on transient current induced in MOS capacitors by heavy ion incidence, Si MOS capacitors were irradiated with gamma-rays up to 60.9 kGy(SiO2). The change in Transient Ion Beam Induced Current (TIBIC) signals due to gamma-ray irradiation was investigated using 15 MeV-oxygen ion microbeams. After gamma-ray irradiation, the peak current of the TIBIC signal vs. bias voltage curve shifted toward negative voltages. This shift can be interpreted in terms of the charge trapped in the oxide. In this dose range, no significant effects of the interface traps induced by gamma-ray irradiation on the TIBIC signals were observed. [ABSTRACT FROM AUTHOR]

Ion Beam Induced Luminescence (IBIL) and Ion Beam Induced Charge Collection (IBICC) have been used to study the efficiency and the homogeneity of the luminescence emission in phosphors. The IBIL imaging was made by using sharply focused ion beams or broad/partially-focused ion beams. Samples were examined to reveal possible distributed crystal-defects that may lead to the inhomogeneity of the luminescence emission. The purpose of the study is to search for suitable thin films that have high homogeneity of luminescence emission and large IBIL efficiency under heavy ion excitation. These films may be placed as a thin layer on the top of microelectronic devices to be analyzed with Ion Photon Emission Microscopy (IPEM). The emission yields were found to be low for organic materials, due to saturation of the light output dependence on the energy deposition of heavy ions. The emission yield of a typical Bicron plastic scintillator is about 70 photons/ion/micron. Inorganic materials may have higher IBIL yields under high-energy and heavy-ion excitation, but the challenging problem is the inhomogeneity of the IBIL emissions. The IBIL image techniques are applied in the investigation of the homogeneity of a GaN epitaxial thin film, a zircon single crystal and a thin layer coated by Thiogallate (EuII) ceramic. [ABSTRACT FROM AUTHOR]