Methods and systems for trimming circuits

• US 8,921,733 B2
• Filed: 04/13/2012
• Issued: 12/30/2014
• Est. Priority Date: 08/11/2003
• Status: Expired due to Fees

• Current Assignee: Rayd LLC
• Original Assignee: Raydiance, Inc. (Coherent Corp.)
• Inventors: Gaudiosi, David, Vaissie, Laurent
• Primary Examiner(s): Ross, Dana
• Assistant Examiner(s): Bae, Gyounghyun
• Application Number:
  US13/446,879
• Publication Number:
  US 20120217230A1
• Time in Patent Office: 991 Days
• Field of Search: 219/121.61, 219/121.62, 219/121.68, 219/121.69, 219/121.71, 219/121.83, 219/121.73, 219/121.76, 219/121.77, 324/71.1, 250/455.11, 250/559.13, 73/120.8, 382141-154, 438/690, 438/940
• US Class Current: 219/121.62
• 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 26/0624 using ultrashort pulses, i.e. pulses of 1ns or less
• CPC Class Codes: B23K 26/351 for trimming or tuning of electrical components
• CPC Class Codes: B23K 26/361 for deburring or mechanical trimming B23K26/351 takes precedence
• CPC Class Codes: B23K 26/40 taking account of the properties of the material involved
• CPC Class Codes: H01C 17/242 by laser trimming by laser in general B23K26/351
• CPC Class Codes: H01L 22/14 for electrical parameters, e.g. resistance, deep-levels, CV, diffusions by electrical means
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps

Abstract

Removing material from the surface of a first circuit comprises generating a first laser pulse using a pulse generator; targeting a spot on the first circuit using a focusing component; delivering the first laser pulse to the spot on the first circuit, the first circuit including a digital component; ablating material from the spot using the first laser pulse without changing a state of the digital component; testing performance of the first circuit, the testing being performed without reinitializing the circuit between the steps of ablating material and testing performance. Targeting the spot on the first circuit comprises generating a second laser pulse using a pulse generator; delivering a second laser pulse to a sacrificial piece of material; detecting the position of the ablation caused by the second laser pulse with a vision system that forms an image; and using this image to guide the first laser to the spot.

Claims

1. A method of removing material from the surface of a first circuit, the method comprising:

generating a first laser pulse using a pulse generator;

targeting a spot on the first circuit using a focusing component;

delivering the first laser pulse to the spot on the first circuit, the first circuit including a digital component;

ablating material from the spot using the first laser pulse without changing a state of the digital component by using the first laser pulse having a wavelength in a near-infrared region and a duration equal or shorter than sub-nanosecond; and

testing performance of the first circuit following the step of ablating material, the testing being performed without reinitializing the circuit between the steps of ablating material and testing performance,

targeting the spot on the first circuit comprises;

generating a second laser pulse using a pulse generator;

delivering a second laser pulse to a sacrificial piece of material;

detecting the position of the ablation caused by the second laser pulse with a vision system that forms an image; and

using this image to guide the first laser to the spot.

2. The method of claim 1, further comprising sensing a composition of the material ablated from the spot.

3. The method of claim 1, wherein the first laser pulse has a wavelength greater than 1100 nanometers and a duration of less than 10 picoseconds.

4. The method of claim 1, wherein the first laser pulse has a wavelength greater than 1350 nanometers.

5. The method of claim 1, wherein the first laser pulse is delivered as a member of a train of pulses having a repetition rate of at least 1 kHz.

6. The method of claim 1, wherein an area from which the material is ablated has a diameter less than a diameter of a diffraction limited focal spot of the first laser pulse.

7. The method of claim 1, wherein ablating the material comprises generating at least 5000 laser pulses including the first laser pulse.

8. The method of claim 1, wherein ablating the material comprises generating at least 500 laser pulses.

9. The method of claim 1, further comprising ablating material from another spot in parallel with the step of ablating material from the spot.

10. The method of claim 1, further including generating a second laser pulse and using the second laser pulse to trim a second circuit in parallel with the first circuit.

11. The method of claim 1, further including ablating material from a second circuit using a second laser pulse and testing performance of the second circuit, in parallel with ablating material from the spot using the first laser pulse and testing performance of the first circuit.

12. The method of claim 1, wherein the step of generating a first laser pulse includes compressing the first laser pulse using an optical fiber.

13. The method of claim 1, wherein the step of generating a first laser pulse includes amplifying the first laser pulse using an optical fiber.

14. A method of removing material from the surface of a first circuit, the method comprising:

generating a first laser pulse using a pulse generator;

targeting a spot on the first circuit using a focusing component;

delivering the first laser pulse to the spot on the first circuit, the first circuit including a digital component;

ablating material from the spot using the first laser pulse without changing a state of the digital component by using the first laser pulse having a wavelength in a near-infrared region and a duration equal or shorter than sub-nanosecond; and

testing performance of the first circuit following the step of ablating material, the testing being performed without reinitializing the circuit between the steps of ablating material and testing performance,

targeting the spot on the first circuit comprises;

generating a second laser pulse using a pulse generator;

delivering a second laser pulse to a sacrificial piece of material;

aligning a visible alignment beam to identify the location of the ablation caused by the second laser pulse; and

using the alignment beam to guide the first laser to the spot.

15. The method of claim 14, further comprising sensing a composition of the material ablated from the spot.

16. The method of claim 14, wherein the first laser pulse has a wavelength greater than 1100 nanometers and a duration of less than 10 picoseconds.

17. The method of claim 14, wherein the first laser pulse has a wavelength greater than 1350 nanometers.

18. The method of claim 14, wherein the first laser pulse is delivered as a member of a train of pulses having a repetition rate of at least 1 kHz.

19. The method of claim 14, wherein an area from which the material is ablated has a diameter less than a diameter of a diffraction limited focal spot of the first laser pulse.

20. The method of claim 14, wherein ablating the material comprises generating at least 5000 laser pulses including the first laser pulse.

21. The method of claim 14, wherein ablating the material comprises generating at least 500 laser pulses.

22. The method of claim 14, further comprising ablating material from another spot in parallel with the step of ablating material from the spot.

23. The method of claim 14, further including generating a second laser pulse and using the second laser pulse to trim a second circuit in parallel with the first circuit.

24. The method of claim 14, further including ablating material from a second circuit using a second laser pulse and testing performance of the second circuit, in parallel with ablating material from the spot using the first laser pulse and testing performance of the first circuit.

25. The method of claim 14, wherein the step of generating a first laser pulse includes compressing the first laser pulse using an optical fiber.

26. The method of claim 14, wherein the step of generating a first laser pulse includes amplifying the first laser pulse using an optical fiber.