120 Nuclear Instruments and Methods in Physics Research B44 (1989) 120-121 North-Holland

BOOK REVIEWS

This section of NIM B will bring reviews of books relevant for the regular readership of the journal. Books for review should be sent to one of the Editors.

PLASMA DIAGNOSTICS, Vol. 2: SURFACE ANAL- YSIS AND INTERACTIONS edited by 0. Auciello and D.L. Flamm (Academic Press, Boston, 1989) pp. x + 337, $79.50, ISBN o-12-067636-2

Level: Specialist Reviewer: Harold Anderson, University of New Mexico

Several years ago at a Materials Research Society Symposium on Plasma Synthesis and Etching of Elec- tronic Materials, H.F. Dylla [l] of the Princeton Plasma Physics Laboratory noted that the boundary plasmas of high temperature, fully ionized magnetic fusion devices have electron temperatures and densities comparable to low temperature, partially ionized discharges of the sort used for plasma processing. I believe it was Dylla who jokingly said on display of a slide showing Princeton’s Tokomak reactor, “Here is our one megawatt rf plasma etch reactor.” Despite the seeming disparities of these two branches of plasma science, the audience responded to his point which was that the basic physical and chemical processes underlying plasma processing were not dissimilar from those of fusion device boundary plasma interactions with confining surfaces and that diagnostic developments in either branch of plasma science may directly impact the other.

Plasma Diagnostics, Volume 2 in a new series of books on Plasma-Materials Interactions, attempts to further this cross-fertilization process by highlighting recent developments in surface analysis and characteri- zation techniques applicable to the broad subject of surfaces exposed to plasmas. The book is a collection of articles by various authors which describes, for the most part, the basic concepts and specific applications of some better known plasma diagnostic techniques. As such, it is not yet the all-inclusive treatise on diagnostic techniques which define the emerging interdisciplinary field of plasma-material interactions; but it is a step in that direction. It is also a timely publication since there is movement in the low temperature plasma processing community to incorporate features such as magnetic and electron cyclotron resonance confinement schemes in next generation plasma reactors. This movement toward higher density plasmas for plasma processing

0168-583X/89/$03.50 0 Elsevier Science Publishers B.V.

(North-Holland)

will undoubtedly bring the high and low temperature

branches of plasma science closer together. The book covers some of the old and some of the

new in terms of plasma diagnostic development. For example, Chapter 5 on “ Interpretation of Plasma Probes for Fusion Experiments” covers the oldest and simplest plasma diagnostic techniques, the Langmuir probe. However, the author does not simply review fusion probe literature; rather, his bias in the chapter is toward interpretation of probe data in high magnetic field plasmas and impurity effects in the edge plasmas of fusion devices. Similarly in Chapter 6, thermal waves and the photoacoustic effect have been a field of study for more than a century; but the major thrust in this section on “Analysis of Surfaces Exposed to Plasmas” is on important new techniques such as Thermal Wave Microscopy for near surface and subsurface imaging. Thermal wave imaging for the evaluation and char- acterization of semiconductor materials has become al- most overnight a standard tool for measuring damage and defect distributions on plasma etched silicon wafers; it is encouraging to see the review article up to date on recent developments. Thermal wave diagnostic tech- niques for analyzing plasma-surface interactions in controlled fusion and plasma spray coatings are covered as well.

Other chapters in the book cover a diverse range of topics including quartz crystal microbalances (QCMs) techniques, elemental analysis techniques (AES, EPS, SIMS, ISS), surface ellipsometry, and ion beam analysis techniques (RBS, ERD, PIXE, NRA). With such a broad range of subjects to be covered, it is clear that these reviews are neither comprehensive surveys of the field, nor are they intended to be used as a textbook for analytic technique. The focus in the chapters is more on brief tutorials and selected examples of plasma-material interactions, chosen so that specialists in plasma re- search and specialists in analytical technique can have more meaningful discussion about the range of diagnos- tic technique options open to them and the value of the data to be collected. Representative examples of the application of these techniques are generally evenly divided between semiconductor plasma processing and fusion devices.

Book Reviews 121

The balance struck between high and low tempera- ture plasma devices in the contents of Volume 2 of this new series is a welcome development, as is the emphasis on understanding the basic physical and chemical processes in plasma-material interactions. My single greatest concern with this book is the cost versus the amount of subject matter covered. Under the topic of surface diagnostic techniques, there are numerous sub- jects which have not been addressed in Volume 2. Chapters on synchroton radiation studies, scanning tun- nelling microscopy, and various novel laser-based, in situ, plasma and surface diagnostic techniques (e.g. sec- ond harmonic generation (SHG) measurements, photo- emission optogalvanic spectroscopy (POGS), reflection

CALCULATED EFFECTIVE STOPPING POWERS AND PROJECTED RANGES FOR H, He, C, N AND 0 PROJECTILES (0.05-500 keV) IN SOME ELE- MENTS AND MATERIALS OF DOSIMETRIC IN- TEREST by I.A.M. Al-Affan (South Bank Polytechnic, London, 1989) 170 pp, softcover, f8.50. ISBN 0-9514455-O-2

Level: Specialist Reviewer: H.H. Andersen, Copenhagen

Accurate neutron dosimetry in radiation biophysics depends on accurate stopping powers and ranges of the particles released by neutron-induced reactions as well as of elastic recoils in the target materials. Charged particles of interest are hence p, d, 3He, (Y, C, N and 0. Of these d and 3He are not treated in the present tables. The energy range covered is 0.05-500 keV. Target materials are H, C, N, 0, H,O, CO,, a number of simple organic gases, plastics and tissue-equivalent materials.

Comparisons to experimental data are only made to a very limited extent. Old friends like Phillips, Reynolds and Ormrod are used once again but it is obvious that the 1977 bibliography by the present reviewer has not been consulted. What is worse is that the more recent, and also more accurate, data have not been consulted either (Baumgart et al., Besenbacher et al., Bauer, Krist et al. to mention a few). And, now really serious, the seminal low-energy hydrogen stopping powers and ranges from the Riser group (even less than 1 keV) have not been used either. Relevant names here are Schou, Borgesen, Sorensen and Nielsen. This low energy region is also covered by Jackson and Eckstein (1982).

The energy range obviously covers both electronic The tables as they stand are nevertheless quite useful and nuclear stopping power regimes. Scattering of the as they will save their users a substantial amount of projectiles is important and there may be large dif- work. It is only a pity that a limited amount of further ferences between projected ranges and path lengths work could have made them much better and further calculated from the continuous slowing down ap- comparisons more trustworthy. Also it would have been proximation (csda). A concept called “effective stop- interesting to see what could have been done with ping power” is introduced but not defined while outlin- simple Monte Carlo programs like TRIM in the low- ing the calculational method. Also, it is not discussed energy region. The pink cover carries the remark “First whether projected ranges is the parameter of interest edition”. Let us hope that the weaknesses will be cor- rather than vector ranges, which could be thought to be rected in a future version, because such tables are in the case as plane sources are usually not of importance great demand by a community that quite often neither for dosimetric applications. Calculation of projected have the background to compile the data, nor the expe- ranges is based on the Schiott (1966) scheme, while the rience to critically judge the tables they use.

FTIR, etc.) are noticeably absent from this volume. Given the rapid developments occurring in these fields, it is logical to presume these topics will be the subject of future volumes. However, for the price of the book, some of these important new techniques would have made welcome and appropriate additions to this text. Nevertheless, the book contains much useful informa- tion; and it would be a valuable addition to technical libraries. This book is highly recommended.

Reference [l] H.F. Dylla and D.M. Manos, in Mater. Res. Sot. Symp.

Proc., eds. R.P.H. Chang and B. Ables, vol. 38 (1985) pp. 3-22.

Watt and Sutcliffe (1972) method is otherwise used as presented at the 3rd Microdosimetry Symposium. Nuclear and electronic stopping powers for the ele- ments have been taken from the Oldenburg and Booz calculations for DNA (EUR 4876 (1972), CEC Brussels). Only for alphas in hydrogen has some updating taken place. Deviations from Bragg’s rule including gas/solid effects are not taken into account. It is not stated whether the hydrogen target gas is H or H,.