Case 3 Extel Extel is a semiconductor manufacturing company. To make silicon wafers, sand is melted...

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Case 3 Extel Extel is a semiconductor manufacturing company. To make silicon wafers, sand is melted and refined to produce silicon ingots. Laser saws slice these ingots into wafers about as thick as a dime and several inches in diameter. The wafers are cleaned and polished, and each one is used to build multiple chips. The company implements outgoing quality control checks before the wafers are shipped to chip fabrication facilities. Wafers are checked for small defects, such as too many microcracks, which come from excessive heat during the manufacturing process. While a few are acceptable, if there are too many or the microcracks are a little too long, that can adversely affect the wafer and thus the effectiveness of the chips that come from it. Wafers are produced in lots of 25 wafers each. During a 24-hour workday 20 lots are sampled and inspected and the number of wafers with excessive microcracks in each lot are recorded as follows: Sample Defective Wafers 1 2 3 4 5 6 7 B 9 10 1 0 1 2 3 1 2 4 4 3 Sample Defective Wafers 11 12 13 14 15 16 17 18 19 20 2 2 1 0 2 3 3 3 2 2 Q11-Construct a p-chart for the company that describes 99.74% (30- 3 sigma) of the random variation in the process, and indicate if the process seems to be out of control at any time. If the total defective wafers are 41, what is the p bar value? (round to three decimals) D Q12- According to the Case 3 Extel what is UCL (Upper control limit) of P-Chart 3 sigma limits? (Round to three decimals) Question 13 Q13- According to the Case 2 Southern Mills Company what is LCL (Lower control limit) of P-Chart using 3 sigma limits? (Round up to zero if required) Question 14 0.35 pts Q14- According to the Case 2 Southern Mills Company is the process in control? 0.35 pts O All the sample observations are within the control limits suggesting that the delivery process is NOT in control. O All the sample observations are not within the control limits suggesting that the delivery process is NOT in control. O All the sample observations are within the control limits suggesting that the delivery process is in control. Case 3 Extel Extel is a semiconductor manufacturing company. To make silicon wafers, sand is melted and refined to produce silicon ingots. Laser saws slice these ingots into wafers about as thick as a dime and several inches in diameter. The wafers are cleaned and polished, and each one is used to build multiple chips. The company implements outgoing quality control checks before the wafers are shipped to chip fabrication facilities. Wafers are checked for small defects, such as too many microcracks, which come from excessive heat during the manufacturing process. While a few are acceptable, if there are too many or the microcracks are a little too long, that can adversely affect the wafer and thus the effectiveness of the chips that come from it. Wafers are produced in lots of 25 wafers each. During a 24-hour workday 20 lots are sampled and inspected and the number of wafers with excessive microcracks in each lot are recorded as follows: Sample Defective Wafers 1 2 3 4 5 6 7 B 9 10 1 0 1 2 3 1 2 4 4 3 Sample Defective Wafers 11 12 13 14 15 16 17 18 19 20 2 2 1 0 2 3 3 3 2 2 Q11-Construct a p-chart for the company that describes 99.74% (30- 3 sigma) of the random variation in the process, and indicate if the process seems to be out of control at any time. If the total defective wafers are 41, what is the p bar value? (round to three decimals) D Q12- According to the Case 3 Extel what is UCL (Upper control limit) of P-Chart 3 sigma limits? (Round to three decimals) Question 13 Q13- According to the Case 2 Southern Mills Company what is LCL (Lower control limit) of P-Chart using 3 sigma limits? (Round up to zero if required) Question 14 0.35 pts Q14- According to the Case 2 Southern Mills Company is the process in control? 0.35 pts O All the sample observations are within the control limits suggesting that the delivery process is NOT in control. O All the sample observations are not within the control limits suggesting that the delivery process is NOT in control. O All the sample observations are within the control limits suggesting that the delivery process is in control.

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Answer Q11 To construct a pchart for Extel we first calculate the proportion of defective wafers for ... View the full answer