d003 <- read.table(here::here("data", "SEMICOND.txt"), header = TRUE)D003. Samples of oxide layers on silicon wafers
The data file can be downloaded here:
In this dataset, the measurements correspond to thickness (thick) of the oxide layer on silicon wafers. The wafers (wafer) were randomly selected from eight different lots (lot), each having 25 wafers in total. After the layer of oxide was deposited, the layer’s thickness was assessed at three randomly selected sites (site) within each wafer. In addition, two different sources (source) of material are available and can be compared statistically (Littell et al. 1996; Pinheiro and Bates 2000).
| source | lot | wafer | site | thick |
|---|---|---|---|---|
| 1 | 1 | 1 | 1 | 2006 |
| 1 | 1 | 2 | 2 | 1988 |
| 1 | 1 | 3 | 3 | 2007 |
| 1 | 2 | 2 | 1 | 1987 |
| 1 | 2 | 3 | 2 | 1983 |
| 1 | 3 | 1 | 3 | 2004 |
| 1 | 3 | 3 | 1 | 1999 |
| 1 | 4 | 1 | 2 | 1994 |