I. INTRODUCTION and SUMMARY
Contributed by K. C. A. Smith

Charles Oatley’s appointment in 1960 to the Chair of Electrical Engineering, and the decision taken in the early 1960s by the Cambridge Instrument Company to manufacture the SEM, marked a turning point in the pattern of research on the SEM in the Department, which hitherto had been directed by Oatley alone. It also began an era of close collaboration between the Engineering Department and the Company (and its successors) that has lasted to the present day. Many Ph.D. students have joined the Company to continue work on the development of the SEM and allied instruments, or to follow other career paths. In this Chapter (which will be found on the associated CUED Website) we record briefly the research projects related to the field of scanning electron microscopy undertaken in the Department from the 1960s onwards. Some of this research has been exploited directly by the Company, or has influenced the direction of its research and development policy. Spin-off from the research has also led to the formation of several small companies within the Cambridge region.

The research undertaken in the Department during this period was directed largely by Bill Nixon, Haroon Ahmed and Ken Smith all of whom, as will be evident from the accounts given in previous chapters, were involved in the events leading to the commercial manufacture of the SEM. Nixon joined the Engineering Department in 1959, and took over the direction of the research on the SEM. Smith, on his return from Canada in 1960, filled the position vacated by Nixon in Cosslett’s group at the Cavendish, but rejoined the Engineering Department in 1965. Ahmed was appointed Demonstrator in the Department in 1963 and Lecturer in 1966. Leslie Peters continued to assist with work on the SEM until his untimely death in 1995; Bernie Breton joined the team in 1981. One of Smith’s research students, David Holburn, was appointed to a Lectureship in 1986, and he and Breton have carried on aspects of research on the SEM to the present time.

With the launch of the Stereoscan in 1965, Oatley began to receive a steady stream of royalties from sales, and with this he set up what became known within the Department as the ‘Stereoscan Fund’. A substantial proportion of this was allocated annually to the triumvirate working on the SEM and, until he left the Department in 1966, to Chris Grigson working on scanning electron diffraction. Oatley also made donations to the research students who took part in the development of the early SEMs. When Oatley retired in 1971, the Fund enabled him to set up a small laboratory to conduct his own individual research on the SEM (see main volume, Chapter 5.1). Throughout most of the period concerned he kept a fatherly eye on the proceedings, and his daily attendance and conversations at the morning coffee break were a source of inspiration to generations of students.

The research undertaken was extremely varied, but was mainly instrumental in nature. Nixon was concerned first with improving the resolving power of the SEM and developing new methods of contrast formation. Later he turned his attention to instrumentation for the testing and manufacture of microcircuits (Section II). Ahmed investigated methods of microfabrication, research that led to the founding of the Microcircuit Engineering Laboratory as an out-station of the CUED on the Cambridge Science Park and, ultimately, to the establishment of the Microelectronics Research Centre at the Cavendish Laboratory (see main volume, Chapter 5.8, and Section III). Smith initially studied the application of field emitters to the SEM, and later took up the application of computers and computer image storage and processing (Section IV). The work of Grigson’s reseach students is described by Dennis McMullan (Section V). Holburn and Breton were concerned with image processing, automation and later, with Nicholas Caldwell, knowledge-based (expert) systems to perform instrument fault diagnosis and optimal operation (see main volume, Chapter 5.5, and Section VI).

In addition to the mainstream research on the SEM, a number of other electron-optically related projects are described briefly on this website. These include Munro’s work on computer-aided design methods (Section VII), and a major collaborative project with Cosslett’s Group in the Cavendish Laboratory on the Cambridge University High Resolution Electron Microscope (Section VIII). The research, which extended over a period of some four decades, is described in the following sections. These include representative figures from each of the dissertations written by the research students engaged in the work.