The depth profile was monitored by the operator, as soon as the carbon signal levelled off, the profile run was finished as it was assumed that the contamination layer had been sputtered off by this time. It is always worthwhile to check the depth profile for features either with or without residue suggesting a contamination feature, as it was sometimes difficult to "see" the moment the signal levelled off.
Depth profiles also provide an excellent overview of contamination layer thicknesses as present on all six major LDEF orientations. If you are interested in contamination patterns, make sure you also look at the pre- and postflight images and the three-dimensional SIMS imaging contamination analyses, available as an MPEG animation from this archive. An example depth profile of a contamination layer thickness analysis on an MOS detector is shown below. The underlying data may be obtained by clicking on the plot. You may then save the data as a text file from the appropriate menu of your application. You may also download the data as HTML file by activating a function probably labeled "Load to Disk" in your viewer. File format is UNIX-type ASCII text file.
The data format is CSV, comma seperated values, which can be imported by most spreadsheets and plot software and is also the standard data format of BASIC text data files on most platforms. The datafile from the depth profile shown above looks like that:
"Title","Sensor 1172" "Date","04-20-1992" "Mass",12.000000 "Counting Time",1.000000 "Sample Offset Voltage",0.000000 "Mass",16.000000 "Counting Time",1.000000 .... "Raster Size",250.000000,"[microns]" "Imaged Field",150.000000,"[microns]" "Channel","Mass 12","Mass 16","Mass 23","Mass 24","Mass 40" 1,0,32257,17926,6470,893 2,21440,5603,18688,5501,1054 3,32776,3223,17219,3080,1324 4,37093,2189,14857,1430,1419 5,34802,1557,11621,842,1103 6,28742,1183,8686,544,779 ...
