Methods for reticle enhancement technology (RET) for use with variable shaped beam (VSB) lithography include determining an initial mask pattern from a desired pattern for a substrate; calculating a first substrate pattern from the initial mask pattern; determining an initial set of VSB shots that will form the initial mask pattern; calculating a simulated mask pattern from the initial set of VSB shots; calculating a second substrate pattern from the simulated mask pattern; and adjusting the initial set of VSB shots, wherein the adjusting of the initial set of VSB shots creates an adjusted set of VSB shots.

The present invention pertains to methods, apparatuses and computer programs for processing an object for lithography. A method for processing an object for lithography comprises: (a) providing a first gas; (b) providing a second gas, the second gas including second molecules capable of performing an inversion oscillation; (c) providing a particle beam in a working region of the object for production of a deposition material in the working region based at least partly on the first gas and the second gas. The second gas is provided with a gas flow rate of less than 5 sccm, preferably less than 2 sccm, more preferably less than 0.5 sccm.

The present invention pertains to methods, apparatuses and computer programs for processing an object for lithography. A method for processing an object for lithography comprises: (a) providing a first gas; (b) providing a second gas, the second gas including second molecules capable of performing an inversion oscillation; (c) providing a particle beam in a working region of the object for production of a deposition material in the working region based at least partly on the first gas and the second gas. The second gas is provided with a gas flow rate of less than 5 sccm, preferably less than 2 sccm, more preferably less than 0.5 sccm.

The present invention relates to a method for determining an alignment of a photomask on a sample stage which is displaceable along at least one axis that is parallel to a chuck surface of the sample stage, and is rotatable about at least one axis that is perpendicular to the chuck surface, which method comprises the following step:

rotating the sample stage by a predefined angle and measuring a height change of the photomask during rotation at a predetermined, non-vanishing distance with respect to the rotation axis for the purpose of determining the alignment of the photomask on the sample stage.

A method includes: providing a photomask used in extreme ultra violet (EUV) lithography; receiving information of the photomask; determining a bias voltage of an electron beam writer system according to the information; and performing a repairing operation on the photomask by the electron beam writer system with the bias voltage.

A method includes: providing a photomask used in extreme ultra violet (EUV) lithography; receiving information of the photomask; determining a bias voltage of an electron beam writer system according to the information; and performing a repairing operation on the photomask by the electron beam writer system with the bias voltage.

A method includes: providing a photomask, wherein the photomask includes a multilayer stack, a light-absorption layer, an anti-reflection coating and a light-absorption layer. The method further includes: receiving information on the photomask; determining a bias voltage according to the information; determining a scan recipe of an electron beam writer system based on the bias voltage; and performing a repairing operation on at least one of the anti-reflection coating and the light-absorption layer by the electron beam writer system with the scan recipe.

A method includes: providing a photomask, wherein the photomask includes a multilayer stack, a light-absorption layer, an anti-reflection coating and a light-absorption layer. The method further includes: receiving information on the photomask; determining a bias voltage according to the information; determining a scan recipe of an electron beam writer system based on the bias voltage; and performing a repairing operation on at least one of the anti-reflection coating and the light-absorption layer by the electron beam writer system with the scan recipe.

The present invention encompasses a method of repairing a defect on a lithography mask, comprising the following steps: (a.) directing a particle beam onto the defect to induce a local etching operation on the defect; (b.) monitoring the etching operation using backscattered particles and/or secondary particles and/or another free-space signal generated by the etching operation, in order to detect a transition from the local etching operation on the defect to a local etching operation on an element of the mask beneath the defect, and (c.) feeding in at least one contrast gas in order to increase contrast in the detection of the transition.

The present invention encompasses a method of repairing a defect on a lithography mask, comprising the following steps: (a.) directing a particle beam onto the defect to induce a local etching operation on the defect; (b.) monitoring the etching operation using backscattered particles and/or secondary particles and/or another free-space signal generated by the etching operation, in order to detect a transition from the local etching operation on the defect to a local etching operation on an element of the mask beneath the defect, and (c.) feeding in at least one contrast gas in order to increase contrast in the detection of the transition.