Rabi Cycling to Generate the New Silicon Wafers

After the Mac OS X, the failure to satisfy the Moore’s law is considered as sign of apocalypse in the industry. The law is a mere conclusion from the patterns observed. According to the phenomenon, the silicon chip features are doubling once in 18 months.

Rabi cycling

A photographic circuit image is etched on to silicon wafer with photolithography techniques. The silicon chip circuit etching is controlled by the diffraction limit of light. The current optical and imaging systems fail to make tinier dots of light due to higher limits. Conventionally silicon wafers are coated with photosensitive chemicals on which a circuit image is projected using a projector. The chemical undergoes reaction upon the interference of light rays and washing in acid removes the unexposed portion of the silicon wafer. Light waves excite the chemical molecules which gets destabilized and susceptible to acid wash.

The Researchers manipulated this reaction to create a stable molecule which exhibits Rabi cycling. Once the chemical molecules are hit by light of suitable wavelength, they get excited to form a stable molecule. When the molecules are exposed to light for sufficient time all of them end up in the stabilized state. Further exposure causes the molecules to cycle between the two states rapidly.

For this Rabi cycling to be effective, you should choose the right wavelength of light and expose the chemical for the right duration to put all molecules in excited state. Also, the duration should be controlled so as to adjust the light intensity. For a lower intensity of light waves, higher duration is required and vice versa.

A laser beam has the highest intensity is in center which gradually declines towards the sides. So even if you are choosing the correct intensity, only the center molecules are sufficiently exposed to get excited. Those molecules on edges fail to get stabilized.

Scientists were able to overcome this drawback by applying a second beam. This is obtained by splitting the first beam intended to create the effect called Rabi cycling. The beams are allowed to excite the molecules and recombined at specific angle.  The interference will create a series of stripes whose centers are laden with the excited molecules. This is hit with a second light beam and the molecules exhibit finer features.

The researchers were able to prove the independent nature of resolutions in relation to the color of light. Even a microwave radiation can produce similar patterns. There are a few backdrops like interference patterns, complexity of the process, and different light sources offering varied photo resistance. Despite all these shortcomings, the research process is to gain momentum in lithographic techniques. Chances are high for the development of a Rabi cycling system with photo resistant features.

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