Laser annealing device and method

Patent metadata

Field	Value
Publication number	US-9257287-B2
Application number	US-201313935265-A
Country	US
Kind code	B2
Filing date	Jul 3, 2013
Priority date	Dec 12, 2012
Publication date	Feb 9, 2016
Grant date	Feb 9, 2016

Abstract

A laser annealing device for compensating wafer heat maps and its method are disclosed. A laser annealing device comprises a pump laser source array including of a plurality of pump laser sources for irradiating a tunable mask, each pump laser source emitting pump laser, an annealing laser source for emitting annealing laser and irradiating the tunable mask, and a tunable mask for transmitting at least part of the annealing laser after being irradiated by the pump laser.

First claim

What is claimed is:

1. A laser annealing device, comprising:
a pump laser source array including a plurality of pump laser sources, the pump laser sources each emitting a pump laser beam;
an annealing laser source for emitting annealing laser; and
a tunable mask for transmitting at least part of the annealing laser after being irradiated by the pump laser beam,
wherein the tunable mask rotates at a predetermined speed, and
wherein the tunable mask has a band gap Eg, the annealing laser has an optical band gap Eb larger than the Eg, and the pump laser beam has an optical band gap Ea larger than the band gap Eb.

2. The device according to claim 1 , wherein the Ea is equal to or larger than 1.5 times of the Eg, and
the Eb is 80˜100 meV larger than the Eg.

3. The device according to claim 1 ,
wherein emitting power of each pump laser source in the pump laser source array is adjusted according to an expected transmittance profile of the tunable mask, and
wherein the expected transmittance profile is calculated using a pre-measured heat map of a wafer to be annealed, the Eg, and the Eb.

4. The device according to claim 1 ,
the plurality of pump laser sources in the pump laser source array are arranged in a first radial direction relative to the rotating axis;
the annealing laser source is arranged in a second radial direction relative to the rotating axis, the second radial direction forms a predetermined angle with the pump laser source array; and
the pump laser source array and the annealing laser source are fixed to the rotating axis, and spaced apart a predetermined distance from the tunable mask along the rotating axis.

5. The device according to claim 4 , wherein the predetermined speed and the predetermined angle of the tunable mask are adjustable so that the emitting power of the each pump laser source in the pump laser source array is calculated using a pre-measured heat map of a wafer to be annealed, the Eg, the Eb, the predetermined speed, the predetermined angle, and the Ea.

6. The device according to claim 1 , further comprising:
a mask with a slit, wherein the annealing laser transmitted through the tunable mask passes through the slit for annealing.

7. The device according to claim 1 , wherein the tunable mask is made of Si, and the annealing laser has a wavelength of 600 nm.

8. The device according to claim 1 , further comprising a plurality of beam expanding lenses located between the respective pump laser sources in the pump laser source array and the tunable mask, and between the annealing laser source and the tunable mask.

Assignees

• Semiconductor Mfg Int Shanghai

Inventors

• Cai Boxiu

Classifications

• H10P14/381

  Beam shaping, e.g. using a mask · CPC title

• H10P95/90

  Thermal treatments, e.g. annealing or sintering · CPC title

• H10P34/40

  with high-energy radiation · CPC title

• H10P34/00

  Irradiation with electromagnetic or particle radiation of wafers, substrates or parts of devices · CPC title

• H10P34/42 Primary

  with electromagnetic radiation, e.g. laser annealing (laser cutting H10P54/20) · CPC title