Systems and methods for forming apertures in microfeature workpieces

• US 8,664,562 B2
• Filed: 05/01/2006
• Issued: 03/04/2014
• Est. Priority Date: 05/05/2004
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Watkins, Charles M., Hiatt, William M.
• Primary Examiner(s): Heinrich, Samuel M
• Application Number:
  US11/414,999
• Publication Number:
  US 20060191882A1
• Time in Patent Office: 2,864 Days
• Field of Search: 219/121.61, 219/121.62, 219/121.7, 219/121.71, 219/121.83
• US Class Current: 219/121.7
• CPC Class Codes: B23K 2101/40 Semiconductor devices
• CPC Class Codes: B23K 2103/50 Inorganic material, e.g. metals, not provided for in B23K2103/02 – B23K2103/26
• CPC Class Codes: B23K 2103/56 semiconducting semiconducting devices B23K2101/40
• CPC Class Codes: B23K 26/03 Observing, e.g. monitoring, the workpiece
• CPC Class Codes: B23K 26/0342 Observing magnetic fields related to the workpiece
• CPC Class Codes: B23K 26/361 for deburring or mechanical trimming B23K26/351 takes precedence
• CPC Class Codes: B23K 26/362 Laser etching
• CPC Class Codes: B23K 26/38 by boring or cutting
• CPC Class Codes: B23K 26/382 by boring
• CPC Class Codes: B23K 26/40 taking account of the properties of the material involved
• CPC Class Codes: H01L 21/486 Via connections through the substrate with or without pins
• CPC Class Codes: H01L 21/76898 formed through a semiconductor substrate
• CPC Class Codes: H05K 2203/163 Monitoring a manufacturing process
• CPC Class Codes: H05K 3/0026 by laser ablation
• CPC Class Codes: Y10T 29/49165 by forming conductive walled aperture in base

Abstract

Systems and methods for forming apertures in microfeature workpieces are disclosed herein. In one embodiment, a method includes directing a laser beam toward a microfeature workpiece to form an aperture and sensing the laser beam pass through the microfeature workpiece in real time. The method can further include determining a number of pulses of the laser beam and/or an elapsed time to form the aperture and controlling the laser beam based on the determined number of pulses and/or the determined elapsed time to form a second aperture in the microfeature workpiece.

Claims

1. A system for forming an aperture in a microfeature workpiece, the system comprising:

a laser configured to produce a laser beam along a beam path;

an electromagnetic radiation sensor positioned along the beam path to sense the laser beam;

a workpiece carrier;

a metrology tool configured to measure a first thickness at a first location and a second thickness at a second location of the microfeature workpiece, the first and second locations being different from each other; and

a controller operably coupled to the laser, the electromagnetic radiation sensor, the metrology tool, and the workpiece carrier, the controller having a computer-readable medium containing instructions to perform a method comprising—

positioning the microfeature workpiece in the beam path with the workpiece carrier;

directing the metrology tool to measure the first thickness at the first location of the microfeature workpiece;

directing the laser beam toward the microfeature workpiece to form the aperture in the microfeature workpiece at the first location;

sensing the laser beam pass through the microfeature workpiece with the electromagnetic radiation sensor;

recording a number of pulses of the laser beam and/or an elapsed time when sensing the laser beam pass through the microfeature workpiece;

directing the metrology tool to measure the second thickness at the second location of the microfeature workpiece; and

controlling the laser beam based on the recorded number of pulses and/or the elapsed time, the first thickness, and the second thickness to form another aperture at the second location of the microfeature workpiece.

2. The system of claim 1 wherein:

the microfeature workpiece includes a first surface and a second surface opposite the first surface; and

the workpiece carrier is configured to carry the microfeature workpiece without contacting a center region of the first surface and a center region of the second surface of the microfeature workpiece.

3. The system of claim 1 wherein the workpiece carrier is configured to engage a perimeter region of the microfeature workpiece to support the workpiece.

4. The system of claim 1 wherein the computer-readable medium contains instructions to perform the method further comprising determining a number of pulses of the laser beam and/or an elapsed time to form the aperture.

5. The system of claim 1 wherein the aperture is a test aperture, and wherein the computer-readable medium contains instructions to perform the method further comprising:

determining a number of pulses of the laser beam and/or an elapsed time to form the test aperture; and

controlling the laser beam based on the determined number of pulses and/or the determined elapsed time to form a plurality of production apertures in the microfeature workpiece.

6. The system of claim 1 wherein the workpiece carrier does not obscure the beam path.

7. A system for forming an aperture in a microfeature workpiece, the system comprising:

a laser configured to produce a laser beam along a beam path;

an electromagnetic radiation sensor positioned along the beam path to sense the laser beam;

a workpiece carrier configured to selectively position the microfeature workpiece in the beam path before the electromagnetic radiation sensor to form the aperture in the microfeature workpiece;

a metrology tool configured to measure a first thickness at a first location and a second thickness at a second location of the microfeature workpiece, the first and second locations being different from each other; and

a controller operably coupled to the laser, the electromagnetic radiation sensor, and the workpiece carrier, and the metrology tool, the controller having a computer-readable medium containing instructions to perform a method comprising—

receiving the first thickness from the metrology tool;

directing the laser beam to form a test aperture in the first location of the microfeature workpiece;

recording a number of pulses of the laser beam and/or an elapsed time to form the test aperture; and

receiving the second thickness from the metrology tool;

controlling the laser beam based on the recorded number of pulses and/or the elapsed time to form the test aperture, the first thickness, and the second thickness to form a production aperture in the second location of the microfeature workpiece.

8. The system of claim 7 wherein controlling the laser beam includes determining a number pulses of the laser beam and/or an elapsed time to form the production aperture based on the recorded number of pulses and/or the elapsed time, the first thickness, and the second thickness.

9. The system of claim 7 wherein controlling the laser beam includes determining a number pulses of the laser beam and/or an elapsed time to form the production aperture by multiplying the recorded number of pulses and/or the elapsed time by a correction factor accounting for a difference in thickness and/or material between the first location and the second location on the microfeature workpiece.

10. The system of claim 7 wherein the workpiece carrier does not obscure the beam path.