(2a) Sketch on three axis plots the following crystal planes: (i) (122) (2 marks) (ii) (11)...

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(2a) Sketch on three axis plots the following crystal planes: (i) (122) (2 marks) (ii) (11) (2 marks) (2b) Wafers supplied often have the terms CZ and FZ applied to them. What do these mean and explain the difference in production of wafers between them? Give two advantages of each type. Which of these two would appear for the largest size of wafers? (8 marks) Substrates for sputter deposition are placed 30 cm below the target. Sputtering is performed using argon. (2c) What type of sputtering is used if the target (and material being deposited) is Aluminum and alternatively if the target is silicon dioxde and why? How does the plasma shape look for each (7 marks each) (2d) Find the argon pressure in microns at which the mean free path in the gas becomes equal to the target substrate distance (molecular diameter = 0.286 nm for Ar) (6 marks) (2a) Sketch on three axis plots the following crystal planes: (i) (122) (2 marks) (ii) (11) (2 marks) (2b) Wafers supplied often have the terms CZ and FZ applied to them. What do these mean and explain the difference in production of wafers between them? Give two advantages of each type. Which of these two would appear for the largest size of wafers? (8 marks) Substrates for sputter deposition are placed 30 cm below the target. Sputtering is performed using argon. (2c) What type of sputtering is used if the target (and material being deposited) is Aluminum and alternatively if the target is silicon dioxde and why? How does the plasma shape look for each (7 marks each) (2d) Find the argon pressure in microns at which the mean free path in the gas becomes equal to the target substrate distance (molecular diameter = 0.286 nm for Ar) (6 marks)