The following sample data were collected to determine the relationship between processing variables and the current gain of a transistor in the integrated circuit:

Fit a regression plane and use its equation to estimate the expected current gain when the diffusion time is 2.2 hours and the sheet resistance is \(90 \Omega-\mathrm{cm}\).

Transcribed Image Text:

Diffusion time Sheet resistance (hours) (N-cm) Current gain XI X2 y 1.5 66 5.3 2.5 87 7.8 0.5 69 7.4 1.2 141 9.8 2.6 93 10.8 0.3 105 9.1 2.4 111 8.1 2.0 78 7.2 0.7 66 6.5 1.6 123 12.6