SEMICONDUCTOR PHYSICS LABORATORY

The course, accounting for 6 CFU (60 hours), provide students with both knowledge and critical sense in issues related to solid state physics. In particular, this course provides a glimpse on the properties of silicon and other semiconductor crystals widely used in electronics industry and research. Different micromachining techniques to process and develop semiconductor crystals suitable for many scientific and industrial applications will be presented. In addition, characterization techniques based on high-resolution x-ray diffraction exploited for the investigation and resolution of various crystallographic problems related to both single and polycrystalline materials, starting from an elementary level, will be introduced.
We expect that at the end of the course, the student will be able to choose which technique is best to use to characterize the structure of a crystalline material, or which method is preferable to use for its processing.

• Basic concepts of solid mechanics. Stresses, deformations, mechanical behavior and constitutive laws of materials (5h).
• Semiconductor crystals. Silicon crystal properties with introduction to the history of the semiconductor industry (5h).
• Crystal characterization via X-ray diffraction. Kinematic theory of diffraction. Introduction of dynamical theory of diffraction. High-resolution X-ray diffraction (HRXRD) and its applications to Crystallography (9h).
• Lab methods for production and detection of X-rays: laboratory sources, X-ray from synchrotron and free electron lasers. Hints on industrial applications (8h).

• Introduction to Silicon Micromachining - techniques to fabricate microdevices and micromachines for functional devices such as micro-sensors, micro-actuators, biochips, etc. Wet bulk-micromachining, reactive ion etching (RIE), deep reactive ion etching (DRIE), surface micromachining, and laser micromachining. Photo- and nano-lithography (6h).
• Laboratory activity on Si micromachining - processing and molding via photolithography techniques (12h).
• Laboratory activity on characterization of semiconductor wafers and micromachined devices via optical interferometry and high-resolution X-ray diffraction in clean room environment. Measurements of interest for the semiconductor industry (15h).

The objective of the exam is to verify the level of achievement of the previously indicated training objectives. It will consist of a laboratory report to which an evaluation will be assigned. The oral exam will verify the student's preparation in dealing with the topics that will be proposed. The laboratory reports are used to assess whether the student has acquired the skills indicated while the oral exam serves to assess whether he has acquired the required knowledge. The final grade will take into account the student's overall preparation resulting from the exam tests (laboratory reports and oral exam).

• Teacher's note
• Textbook "The Basics of Crystallography and Diffraction", Christopher Hammond