Method and device for characterizing an electron beam using an X-ray detector with a patterned aperture resolver and patterned aperture modulator

• US 9,406,483 B1
• Filed: 12/17/2015
• Issued: 08/02/2016
• Est. Priority Date: 01/21/2015
• Status: Active Grant

• Current Assignee: Arcam Ab (Danaher Corporation)
• Original Assignee: Arcam Ab (Danaher Corporation)
• Inventors: Lock, Tomas
• Primary Examiner(s): MCCORMACK, JASON L
• Application Number:
  US14/973,244
• Publication Number:
  US 20160211119A1
• Time in Patent Office: 229 Days
• Field of Search: 250/305, 250/306, 250/307, 250/311, 250/492.1, 250/492.3
• US Class Current: 1/1
• CPC Class Codes: B22F 10/28 Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
• CPC Class Codes: B22F 10/31 Calibration of process steps or apparatus settings, e.g. before or during manufacturing
• CPC Class Codes: B22F 12/44 characterised by the configuration of the radiation means
• CPC Class Codes: B22F 12/49 Scanners
• CPC Class Codes: B22F 12/55 Two or more means for feeding material
• CPC Class Codes: B22F 12/90 Means for process control, e.g. cameras or sensors
• CPC Class Codes: B23K 15/0013 Positioning or observing workpieces, e.g. with respect to the impact; Aligning, aiming or focusing electronbeams
• CPC Class Codes: B23K 15/002 Devices involving relative movement between electronbeam and workpiece
• CPC Class Codes: B23K 15/0026 Auxiliary equipment
• CPC Class Codes: B23K 15/0086 welding for purposes other than joining, e.g. built-up welding
• CPC Class Codes: B23K 15/02 Control circuits therefor
• CPC Class Codes: B28B 1/001 Rapid manufacturing of 3D objects by additive depositing, agglomerating or laminating of material selective deposition modelling of metallic powder B22F10/00; rapid manufacturing of 3D objects in general and in particular of plastics B29C64/00
• CPC Class Codes: B28B 17/00 Details of, or accessories for, apparatus for shaping the material; Auxiliary measures taken in connection with such shaping moulds B28B7/00; after-treatment B28B11/00; feeding or discharging B28B13/00; arrangements for embedding elements in the material B28B23/00
• CPC Class Codes: B28B 17/0081 Process control
• CPC Class Codes: B29C 64/153 using layers of powder being selectively joined, e.g. by selective laser sintering or melting
• CPC Class Codes: B29C 64/364 Conditioning of environment
• CPC Class Codes: B29C 64/393 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 40/00 Auxiliary operations or equipment, e.g. for material handling
• CPC Class Codes: B33Y 50/02 : for controlling or regulating additive manufacturing processes
• CPC Class Codes: G01T 1/295 : using coded aperture devices, e.g. Fresnel zone plates handling of radiation of particles, e.g. using diaphragms, collimators, diffraction G21K1/00
• CPC Class Codes: H01J 2237/0453 : multiple apertures
• CPC Class Codes: H01J 2237/2445 : Photon detectors for X-rays, light, e.g. photomultipliers
• CPC Class Codes: H01J 2237/2448 : Secondary particle detectors
• CPC Class Codes: H01J 2237/24514 : Beam diagnostics including control of the parameter or property diagnosed H01J2237/30472 takes precedence
• CPC Class Codes: H01J 2237/2826 : Calibration
• CPC Class Codes: H01J 2237/30433 : System calibration
• CPC Class Codes: H01J 2237/3045 : Deflection calibration
• CPC Class Codes: H01J 2237/30472 : Controlling the beam
• CPC Class Codes: H01J 2237/3128 : Melting
• CPC Class Codes: H01J 37/09 : Diaphragms; Shields associated with electron or ion-optical arrangements; Compensation of disturbing fields
• CPC Class Codes: H01J 37/244 : Detectors; Associated components or circuits therefor
• CPC Class Codes: H01J 37/30 : Electron-beam or ion-beam tubes for localised treatment of objects
• CPC Class Codes: H01J 37/3005 : Observing the objects or the point of impact on the object
• CPC Class Codes: H01J 37/304 : Controlling tubes by information coming from the objects or from the beam, e.g. correction signals
• CPC Class Codes: H01J 37/3045 : Object or beam position registration
• CPC Class Codes: H01J 37/305 : for casting, melting, evaporating, or etching
• CPC Class Codes: H01J 37/317 : for changing properties of the objects or for applying thin layers thereon, e.g. for ion implantation H01J37/36 takes precedence
• CPC Class Codes: Y02P 10/25 : Process efficiency

Abstract

A device for detecting X-rays radiated out of a substrate surface, said device comprising at least one X-ray detector, a resolver grating and a modulator grating, said resolver grating with at least one opening facing towards said X-ray detector is arranged in front of said X-ray detector. Said modulator grating is provided between said resolver grating and said substrate at a predetermined distance from said resolver grating and said substrate, where said modulator grating having a plurality of openings in at least a first direction, wherein said x-rays from said surface is spatially modulated with said modulator grating and resolver grating.

Claims

1. A method for verifying an electron beam, said method comprising the steps of:

arranging a patterned aperture resolver having at least one opening in front of at least one X-ray detector, where said at least one opening is facing towards said at least one X-ray detector;

arranging a patterned aperture modulator between said patterned aperture resolver and a substrate and at a predetermined distance from said patterned aperture resolver and said substrate, said patterned aperture modulator having a plurality of openings in at least a first direction;

scanning an electron beam in at least said first direction on said substrate for generating X-rays to be received by said at least one X-ray detector; and

verifying at least one of a position, size and shape of said electron beam by comparing a detected intensity modulation of said X-ray signal by said detector with corresponding reference values, wherein said electron beam is said to be verified if a deviation of said detected intensity modulation and said reference value is smaller than a predetermined value.

2. The method according to claim 1, wherein said scanning and verifying steps are repeated for different beam powers.

3. The method according to claim 1, wherein:

said reference values are stored within one or more memory storage areas; and

at least said verifying step is performed via at least one computer processor.

4. A program element configured and arranged when executed on a computer to implement a method for verifying an electron beam, said method comprising the steps of:

arranging a patterned aperture resolver having at least one opening in front of at least one X-ray detector, where said at least one opening is facing towards said at least one X-ray detector;

arranging a patterned aperture modulator between said patterned aperture resolver and a substrate and at a predetermined distance from said patterned aperture resolver and said substrate, said patterned aperture modulator having a plurality of openings in at least a first direction;

scanning an electron beam in at least said first direction on said substrate for generating X-rays to be received by said at least one X-ray detector; and

verifying at least one of a position, size and shape of said electron beam by comparing a detected intensity modulation of said X-ray signal by said detector with corresponding reference values, wherein said electron beam is said to be verified if a deviation of said detected intensity modulation of said X-ray signal and said reference value is smaller than a predetermined value.

5. A non-transitory computer readable medium having stored thereon the program element according to claim 4.

6. A non-transitory computer program product comprising at least one non-transitory computer-readable storage medium having computer-readable program code portions embodied therein, the computer-readable program code portions comprising:

an executable portion configured for arranging a patterned aperture resolver having at least one opening in front of at least one X-ray detector, where said at least one opening is facing towards said at least one X-ray detector;

an executable portion configured for arranging a patterned aperture modulator between said patterned aperture resolver and a substrate and at a predetermined distance from said patterned aperture resolver and said substrate, where said patterned aperture modulator having a plurality of openings in at least a first direction;

an executable portion configured for scanning an electron beam in at least said first direction on said substrate for generating X-rays to be received by said at least one X-ray detector; and

an executable portion configured for verifying at least one of a position, size and shape of said electron beam by comparing a detected intensity modulation of said X-ray signal by said detector with corresponding reference values, wherein said electron beam is said to be verified if a deviation of said detected intensity modulation of said X-ray signal and said reference value is smaller than a predetermined value.