A mixed architecture light curtain system comprises a mix of flexibly and rigidly interconnected light curtain segments. The system includes a bin with an auger hole formed on one end in which an auger nozzle is inserted. The apparatus further includes an illumination system for illuminating the interior of the hole. In some examples, the composition may be administered 1-3 times weekly. Memory elements lie in a multi-layer array of interface regions at cross-points between side surfaces of the semiconductor material strips on the stacks and the conductive lines. In one embodiment, the nitride compound includes SixNy.