Patent ID: 11476081

Abstract:
A method, non-transitory computer readable medium and an evaluation system for evaluating an intermediate product related to a three dimensional NAND memory unit. The evaluation system may include an imager and a processing circuit. The imager may be configured to obtain, via an open gap, an electron image of a portion of a structural element that belongs to an intermediate product. The structural element may include a sequence of layers that include a top layer that is followed by alternating nonconductive layers and recessed conductive layers. The imager may include electron optics configured to scan the portion of the structural element with an electron beam that is oblique to a longitudinal axis of the open gap. The processing circuit is configured to evaluate the intermediate product based on the electron image. The open gap (a) exhibits a high aspect ratio, (b) has a width of nanometric scale, and (c) is formed between structural elements of the intermediate product.