Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Laser spectral engineering for lithographic process










Image Number 16 for United States Patent #6671294.

An integrated circuit lithography technique called spectral engineering by Applicants, for bandwidth control of an electric discharge laser. In a preferred process, a computer model is used to model lithographic parameters to determine a desired laser spectrum needed to produce a desired lithographic result. A fast responding tuning mechanism is then used to adjust center wavelength of laser pulses in a burst of pulses to achieve an integrated spectrum for the burst of pulses approximating the desired laser spectrum. The laser beam bandwidth is controlled to produce an effective beam spectrum having at least two spectral peaks in order to produce improved pattern resolution in photo resist film. Line narrowing equipment is provided having at least one piezoelectric drive and a fast bandwidth detection control system having a time response of less than about 2.0 millisecond. In a preferred embodiment, a wavelength tuning mirror is dithered at dither rates of more than 500 dithers per second in phase with the repetition rate of the laser. In one case, the piezoelectric drive was driven with a square wave signal and in a second case it was driven with a sine wave signal. In another embodiment, the maximum displacement was matched on a one-to-one basis with the laser pulses in order to produce a desired average spectrum with two peaks for a series of laser pulses. Other preferred embodiments utilize three separate wavelength tuning positions producing a spectrum with three separate peaks.








 
 
  Recently Added Patents
Power generating apparatus of renewable energy type and method of attaching and detaching blade
Image reproduction system and image reproduction processing program
Polyureas made from aminocrotonates and enaminones
Stable light source device
Image forming system, printing control method, and program
Solid state lighting devices with cellular arrays and associated methods of manufacturing
Shot scent dispenser
  Randomly Featured Patents
Tumberless automobile ignition lock
Blanket array adhesion system
Digital camera and control method for the same
Method for charging a secondary battery and charger used therefor using constant current and constant voltage
Display screen with a set of icons
Method of fabrication a curved glass sheet with a conductive oxide coating
Multi-purpose holder installed in a vehicle
Circle cutting accessory for a powered rotary hand tool
Image forming apparatus
Ladder module