6 research outputs found
RF performance increase allowing IC timing adjustments by use of backside FIB processing
No full textExtended Circuit Edit, Analysis and Trimming Capabilities Based on the Backside Focused Ion Beam Created Ultra Thin Silicon Platform
No full text2D modelling of polycrystalline silicon thin film solar cells
No full textThe influence of grain boundary (GB) properties on device parameters of polycrystalline silicon (poly-Si) thin film solar cells is investigated by two-dimensional device simulation. A realistic poly-Si thin film model cell composed of antireflection layer, (n+)-type emitter, thick p-type absorber, and (p+)-type back surface field was created. The absorber consists of a low-defect crystalline Si grain with an adjacent highly defective grain boundary layer. The performances of a reference cell without GB, one with n-type and one with p-type GB, respectively, are compared. The doping concentration and defect density at the GB are varied. It is shown that the impact of the grain boundary on the poly-Si cell is twofold: a local potential barrier is created at the GB, and a part of the photogenerated current flows within the GB. Regarding the cell performance, a highly doped n-type GB is less critical in terms of the cell’s short circuit current than a highly doped p-type GB, but more detrimental in terms of the cell’s open circuit voltage and fill factor
Trimming of IC timing and delay by backside FIB processing - comparison of conventional and strained technologies
No full text2D modelling of polycrystalline silicon thin film solar cells
No full textThe influence of grain boundary (GB) properties on device parameters of polycrystalline silicon (poly-Si) thin film solar cells is investigated by two-dimensional device simulation. A realistic poly-Si thin film model cell composed of antireflection layer, (n+)-type emitter, thick p-type absorber, and (p+)-type back surface field was created. The absorber consists of a low-defect crystalline Si grain with an adjacent highly defective grain boundary layer. The performances of a reference cell without GB, one with n-type and one with p-type GB, respectively, are compared. The doping concentration and defect density at the GB are varied. It is shown that the impact of the grain boundary on the poly-Si cell is twofold: a local potential barrier is created at the GB, and a part of the photogenerated current flows within the GB. Regarding the cell performance, a highly doped n-type GB is less critical in terms of the cell’s short circuit current than a highly doped p-type GB, but more detrimental in terms of the cell’s open circuit voltage and fill factor
Grain boundary light beam induced current A characterization of bonded silicon wafers and polycrystalline silicon thin films for diffusion length extraction
No full textThe charge carrier lifetime and accordingly the diffusion length in polycrystalline semiconductor materials is known to be detrimentally influenced by disordered interfaces like grain boundaries GBs . The GB light beam induced current GB LBIC technique is suitable for the extraction of the minority charge carrier diffusion length in unprocessed polycrystalline materials. This measurement method is based on the GB itself acting as a charge collector. A spatially resolved light beam induced current can thus be measured even without a collecting p n junction or Schottky contact, and without biasing the sample. In this contribution we present a simulation based analysis of measured GB LBIC line scans on bonded silicon wafers and polycrystalline silicon thin films with different laser wavelengths and intensitie
