Columbia Technology Ventures

Sequential lateral solidification technique for high performance, polysilicon film production

This technology is a lateral growth process technique that involves laser melting and subsequent crystallization of amorphous silicon using multiple scans to produce thin film polysilicon.

Unmet Need: Polysilicon film fabrication process with decreased effect of non-uniformity

Current methods of producing polysilicon films have unacceptable levels of non-uniformity that can be random or periodic. Chiefly responsible is the fact that the laser beams utilized often have non-uniformities in shape and energy along their length. Consequently, these non-uniformities impact display brightness and performance on the resulting film.

The Technology: Sequential lateral solidification method with sideway capability and improved uniformity

This technology involves using multiple scans of laser pulses to crystallize silicon. With this approach, both random and periodic non-uniformities are greatly mitigated in the resulting thin film transistor. Additionally, this method is able to allow for sideway translation and modulation of stage scan velocity to control the final crystallization product. This will result in significant improvements in device uniformity and performance, thereby making the existing processes useful for next generation video displays and thin film solar cells.

Applications:

  • Active matrix display technology
  • Active-matrix liquid-crystal display technology
  • Thin film solar cells
  • Non-planar integrated circuits

Advantages:

  • Produces more uniform thin film transistors
  • Multiple scans allows for sideways translation
  • Able do modulate different beam intensities for different segments
  • Allows for precise control and adjustment of laser pulse

Lead Inventor:

James Im, PhD

Patent Information:

Patent Status

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