Fractional Factorial Designs with Blocks and Center Points

Experimental Objective

At a plant where integrated circuit chips are fabricated, engineers want to screen for important effects in the etch process. For this experiment, they investigated the five factors and two responses listed in Table 5.1.

Table 5.1: Variables of the IC Fabrication Screening Experiment

Type	Name	Low	High	Description
Factors	TEMP	1210	1220	Deposition temp (C)
	FLOW	55	60	Arsenic flow rate
	TIME	10	16	Deposition time
	ETCH	1180	1220	Etch rate
	ACID	6	14	Acid flow rate
Responses	THCKNESS			Thickness of film
	RESTIVTY			Resistivity

Since this experiment is run over two days, the design will have two blocks.

The goal of this experiment is to identify important factors for further study. These important factors are ones that significantly influence film thickness or resistivity.

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Task List