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Basic model for thermal oxidation of silicon

basic model for thermal oxidation of silicon

Explain the basic model for thermal oxidation of silicon?   Solution:   Model assumptions: This model is valid for a temperature range of 700-1300C, 0.2 – 1 atm pressure, and oxide thickness of 300 – 20,000 Angstrom. The oxidizing species- 1. are transported from the bulk gas phase to gas-oxide …

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Explain different oxide charges?

explain different oxide charges

Explain different oxide charges?   Question: With the necessary diagram, write the name of different charges those are trapped at the Si-SiO2 interface. Also, explain how the charges can be reduced? or Question: Explain different oxide charges and explain how the charges can be reduced?   Solution: The Si-SiO2 interface …

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Factor that affect the oxide growth rate

Factor that affect the oxide growth rate

Q: What are the factor that affect the oxide growth rate?   Solution: Factors affecting the oxide growth rate The crystal orientation of Si affects the oxide growth rate because the reaction rate constant depends on the crystal structure of the Si surface. Any unintentional moisture accelerates the dry oxidation …

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Why wet oxidation rate higher than dry oxidation rate?

Why wet oxidation rate higher than dry oxidation rate

Why wet oxidation rate higher than dry oxidation rate?   Values of C* (Concentrations) for O2 and H2O species in SiO2 at 1000°C are 5.2 x 1016 and 3.0 x 1019  respectively. Again flux of oxidant is proportional to C*, which is almost three orders of magnitude greater for water than for …

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Explain photolithography process

Explain photolithography process

Question: What is lithography? Explain photolithography process?   Solution: Lithography Lithography is the process of transferring patterns of geometric shapes in a mask to a thin layer of radiation-sensitive material (called resist) covering the surface of a semiconductor wafer. লিথোগ্রাফি হল একটি স্থানান্তর প্রক্রিয়া যার মাধ্যমে জ্যামিতিক আকারের একটি সেমিকন্ডাক্টর …

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