A method for forming a semiconductor device structure is provided. The method includes forming a first overlay grating over a substrate. The method includes forming a layer over the first overlay grating. The method includes forming a second overlay grating over the layer. The second overlay grating has a third strip portion and a fourth strip portion, the third strip portion and the fourth strip portion are elongated in the first elongated axis and are spaced apart from each other, there is a second distance between a third sidewall of the third strip portion and a fourth sidewall of the fourth strip portion, the third sidewall faces away from the fourth strip portion, the fourth sidewall faces the third strip portion, the first distance is substantially equal to the second distance, and the first trench extends across the third strip portion and the fourth strip portion.

This disclosure relates to a structure for aligning layers of an integrated circuit (IC) structure that may include a first dielectric layer positioned above a semiconductor substrate having one or more active devices, a trench stop layer positioned above the first dielectric layer, a second dielectric layer positioned above the trench stop layer, and a plurality of metal-filled marking trenches extending vertically through the second dielectric layer and the trench stop layer and at least partially into the first dielectric layer. The metal-filled trenches are electrically isolated from any active devices contained in the IC.

In an exemplary method, a first layer is formed on a substrate. First overlay marks are formed in a first zone of the first layer. A non-transparent layer is formed on top of the first layer. At least a portion of the non-transparent layer is removed from an area above the first zone of the first layer. This provides optical access to the first overlay marks. A second layer is formed on top of the non-transparent layer. Second overlay marks are formed in a second zone of the second layer. Position information is obtained from each of the first overlay marks and the second overlay marks.

In one embodiment, a charged particle beam writing apparatus includes a writer writing a pattern on a substrate on a stage with a charged particle beam, a mark substrate disposed on the stage and having a mark, an irradiation position detector detecting an irradiation position of the charged particle beam on a mark surface, a height detector detecting a surface height of the substrate and the mark substrate, a drift correction unit calculating an amount of drift correction, and a writing control unit correcting the irradiation position of the charged particle beam by using the amount of drift correction. The mark substrate has a pattern region with a plurality of marks and a non-pattern region with no pattern therein, and at least part of the non-pattern region is disposed between different portions of the pattern region. The height detector detects a height of a detection point in the non-pattern region.

Wafer alignment with restricted visual access has been disclosed. In an example, a method of processing a substrate for fabricating a solar cell involves supporting the substrate over a stage. The method involves forming a substantially opaque layer over the substrate. The substantially opaque layer at least partially covers edges of the substrate. The method involves performing fit-up of the substantially opaque layer to the substrate. The method involves illuminating the covered edges of the substrate with light transmitted through the stage, and capturing a first image of the covered edges of the substrate based on the light transmitted through the stage. The method further includes determining a first position of the substrate relative to the stage based on the first image of the covered edges. The substrate may be further processed based on the determined first position of the substrate under the substantially opaque layer.

A detection apparatus that detects a mark formed on a substrate is provided. The detection apparatus includes a substrate holder configured to hold the substrate, an optical system accommodated in the substrate holder, an image sensor configured to capture an image of the mark from the reverse surface side of the substrate through the optical system, and a processor configured to perform detection processing for the mark based on the image of the mark captured by the image sensor. The processor corrects a detection value of the mark based on the position of the mark on the substrate in the height direction and information concerning the telecentricity of the optical system.

Disclosed is a lithography process on a sample including at least one structure and covered by at least a lower layer of resist and a upper layer of resist the process including: using an optical device to image or determine, in reference to the optical device, a position of the selected structure and positions of markers integral with the sample; using an electron-beam device, imaging or determining the position of each marker in reference to the electron-beam device; deducing the position of the selected structure in reference to the electron-beam device; exposing to an electron beam the upper layer of resist above the position of the selected structure to remove all the thickness of the upper layer of resist above the position of the selected structure but none or only part of the thickness of the lower layer of resist above the position of the selected structure.

In a beam irradiation apparatus in which a movable body holds an object, a mark detection system detects a first mark on the movable body while moving the movable body in a first direction and changing an irradiation position of a measurement beam in the first direction, the mark detection system detects a second mark while moving the movable body in the first direction and changing the irradiation position of the measurement beam in the first direction, a controller controls a position of the movable body in a second direction intersecting he first direction during a time period between the detection of the first mark and the detection of the second mark, and the controller controls the movement of the movable body to adjust a positional relation between the object on the movable body and a processing beam, based on results of the detection of the first and second marks.

Provided is a manufacturing method of a semiconductor apparatus including: detecting a position by detecting positional deviation of the upper surface mark and the lower surface mark, by acquiring an upper surface image obtained by observing the upper surface mark from above the upper surface of the semiconductor substrate and a lower surface image obtained by observing the lower surface mark through the semiconductor substrate from above the upper surface of the semiconductor substrate; and forming an element by forming a semiconductor element in the semiconductor substrate, where in a top view in which the upper surface mark and the lower surface mark are projected onto a plane parallel to the upper surface, one of the upper surface mark and the lower surface mark is larger than an other, and the one entirely covers the other.

A wafer alignment apparatus includes a light source, a light detection device, and a rotation device configured to rotate a wafer. The light source is configured to provide a light directed to the wafer. The light detection device is configured to detect reflected light intensity from the wafer to locate at least one wafer alignment mark of wafer alignment marks separated by a plurality of angles. At least two of those angles are equal.