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Semiconductor/Microsystems education is in growing demand due to the demand to bring semiconducting manufacturing back to the USA. At the University of New Mexico (UNM), we have six courses that teach different aspects of semiconductor/microsystems manufacturing from theory to hands-on experience. The Advanced Microfabrication course is a multidisciplinary graduate course that is taken by students with various background and primarily from two different programs i) Nanoscience and Microsystems Engineering (NSME) Program (an interdisciplinary program across various schools and departments) and ii) students from the Mechanical Engineering Department. The course typically consists of a series of lectures along with hands-on microfabrication labs in a cleanroom which were designed to complement the lectures. The course material is multidisciplinary with topics ranging from chemistry, physics, mechanical engineering, electrical engineering, chemical engineering, statistics, material science and biomedical. This comparison study investigates several factors such as lab components, synchronous online versus in-person lectures, and students discipline to determine impact on the final exam (performance) in the course. Based on n=99 students over seven years it was determined that students from the interdisciplinary programs performed better with an average score of 64.04 ±13.26% compared to ME students 55.02 ±16.81%. It was also determined that both in-person lectures and students participating in labs had a significant impact on their final exam grades. Students who attended in-person lectures scored an average of 64.35 ± 15.11% whereas online students scored 51.81 ±14.77%, that is an increase of 12.54%. Students attending hands-on labs also had a significant impact resulting in a 10.17% increase in scores. The results demonstrate that the multidisciplinary material of advanced semiconductor manufacturing is potentially best learned through a combination of in-person lectures and hands-on lab experience and that students who have a more interdisciplinary background are likely to perform better due to the multidisciplinary course contents. 

Micro-scale kinetic energy harvesters are in large demand to function as sustainable power sources for wireless sensor networks and the Internet of Things. However, one of the challenges associated with them is their inability to easily tune the frequency during the manufacturing process, requiring devices to be custom-made for each application. Previous attempts have either used active tuning, which consumes power, or passive devices that increase their energy footprint, thus decreasing power density. This study involved developing a novel passive method that does not alter the device footprint or power density. It involved creating a proof mass with an array of chambers or cavities that can be individually filled with liquid to alter the overall proof mass as well as center of gravity. The resonant frequency of a rectangular cantilever can then be altered by changing the location, density, and volume of the liquid-filled mass. The resolution can be enhanced by increasing the number of chambers, whereas the frequency tuning range can be increased by increasing the amount of liquid or density of the liquids used to fill the cavities. A piezoelectric cantilever with a 340 Hz initial resonant frequency was used as the testing device. Liquids with varying density (silicone oil, liquid sodium polytungstate, and Galinstan) were investigated. The resonant frequencies were measured experimentally by filling various cavities with these liquids to determine the tuning frequency range and resolution. The tuning ranges of the first resonant frequency mode for the device were 142–217 Hz, 108–217 Hz, and 78.4–217 Hz for silicone oil, liquid sodium polytungstate, and Galinstan, respectively, with a sub Hz resolution. 

Not AvailableWith a high demand to fill jobs in the semiconductor manufacturing due to the Chips Act there is a need to increase job readiness in graduate education, as industry members think current graduate students are not well prepared to transition from academia to industry. Current graduate academic education pedagogy does an excellent job of providing students with knowledge and scientific skills, such as technical writing and communication. However, current graduate education often does not fully prepare students for industry. Students can get the necessary experience through an internship, but this is not always possible due to location, research time constraints, citizenship, and academic time commitments. Students often struggle with transitioning from an academic setting to industry, because they have only ever experienced academia, and most faculty teaching students have little or not experience working in industry. To overcome this challenge, we developed a novel two course curriculum that aims to mimic a semiconductor industry internship. This is accomplished through “role-playing” courses where students act as internships in the 1st semester (onboarding) and then they transition to employees in the second semester, where they will work with other “students/employees” on creating a “startup” microsystem company. The instructors act as Program Managers/ boses. The courses use problem-based learning (PBL) in a nanofabrication cleanroom. The courses are designed to give students hands-on experience to provide them with the knowledge, skills, and abilities (KSA) that are needed in industry. The key KSA’s were determined by an industrial panel of process engineers via a survey which was used to determine which KSA industry (multinational and SME) value the most. The same survey was given to faculty members to compare differences between what faculty and industry value as critical KSA’s needed in the semiconductor industry. To determine where the gaps were between traditional graduate courses and industry a survey listing 48 different KSA’s was provided to both industrial members and engineering faculty. The survey allowed the industry panel to state what KSA’s were important and what KSA’s they thought Universities already do a good job of teaching to graduate students. The initial results showed that the industry panel thought 37.5% of the KSA’s were important and lacking in current graduate education. That means 63.5% of the KSA’s were either not important or that universities already do a good job of teaching those KSA’s. However, engineering faculty said 58.33% of the KSA’s were needed and not currently taught. This shows a strong discrepancy between what Professors think and what industry consider necessary KSA’s. The KSA topics were divided into categories and the ones with the largest discrepancy between faculty and industry were essential skills and statistics. The results of this study will be beneficial to other programs that wish to provide similar experiences for their graduate students. 

Microelectromechanical Systems (MEMS) packaging is over 80% of the cost of a typical MEMS device because there are no standard packaging methods, and each device requires unique packaging. Recently several MEMS devices have illustrated the desire to have a liquid filled cavity within the MEMS device for applications such as biomedical sensors, tunable energy harvesters, or liquid cooling microelectronics. However, embedded liquids in silicon pose a challenge when it comes to packaging. This paper illustrates a novel concept of using a conformal parylene coating to cap or encapsulate the liquid. The concept is validated using various liquids such as various viscosity silicone oils as well as Galinstan a Ga-based liquid metal. The study investigates the packaging reliability through a series of systematic accelerated life-time testing, elevated temperature testing, accelerated soak testing, and mechanical testing (shock and resonant frequency testing). Mass changes were monitored and compared to control (no capping), glass epoxy bonded packaging, and silicone spray coating encapsulation. The results demonstrate the superior mean-time-to-failure of the parylene capping method compared to the other methods. The results confirm that parylene can be used to package embedded liquids in silicon or 3D printed structures. 

The inability to tune the frequency of MEMS vibration energy-harvesting devices is considered to be a major challenge which is limiting the use of these devices in real world applications. Previous attempts are either not compatible with microfabrication, have large footprints, or use complex tuning methods which consume power. This paper reports on a novel passive method of tuning the frequency by embedding solid microparticle masses into a stationary proof mass with an array of cavities. Altering the location, density, and volume of embedded solid filler will affect the resonant frequency, resulting in tuning capabilities. The experimental and computational validation of changing and tuning the frequency are demonstrated. The change in frequency is caused by varying the location of the particle filler in the proof mass to alter the center of gravity. The goal of this study was to experimentally and numerically validate the concept using macro-scale piezoelectric energy-harvesting devices, and to determine key parameters that affect the resolution and range of the frequency-tuning capabilities. The experimental results demonstrated that the range of the frequency tuning for the particular piezoelectric cantilever that was used was between 20.3 Hz and 49.1 Hz. Computational simulations gave similar results of 23.7 Hz to 49.4 Hz. However, the tuning range could be increased by altering the proof mass and cantilever design, which resulted in a tuning range from 144.6 Hz to 30.2 Hz. The resolution of tuning the frequency was <0.1 Hz 

Abstract Arrays of flexible polymer piezoelectric film cantilevers that mimic grass or leaves is a prospective idea for harvesting wind energy in urban areas, where the use of traditional technologies is problematic due to low wind velocities. Conversion of this idea into an economically attractive technology depends on various factors including the shape and dimensions of individual films to maximize generated power and to minimize associated costs of production, operation, and maintenance. The latter requirement can be satisfied with rectangular films undergoing flutter in ambient air. Flexible piezoelectric films that displace due to low forces and can convert mechanical energy into electrical energy are ideal for this application. The goal of the presented study is to determine the key dimensions of the piezoelectric film to enhance generated power within the wind range characteristic for urban areas from 1.3 to 7.6 m/s. For this purpose, experiments were conducted in a wind tunnel using piezoelectric polymer films of polyvinylidine fluoride with the length, width, and thickness varying in the ranges of 32–150, 16–22, and 40–64 μm, respectively. Voltage and power outputs for individual samples were measured at wind speeds ranging from 0.5 to 16.5 m/s. Results demonstrated that a single film could produce up to 0.74 nW and that the optimal film dimensions are 63 mm × 22 mm × 40 μm (from considered samples) for the wind energy harvesting in urban areas. Further improvement in power production can be expected when using films with reduced thickness, low elastic modulus, and increased length, and by assembling films in arrays. 

Providing hands-on learning experiences increases student understanding of theory and practices in STEM (science, technology, engineering, and mathematics) fields. The experience gives students motivation and allows them to focus their career path towards completing a degree in a STEM field. This paper provides initial observations on the learning impact of community college students and their instructors participating in the Support Center for Microsystems Education 2021 Undergraduate Research Experience. Twenty undergraduate community college students and their instructors participated in a week-long hands-on project-based course in a cleanroom environment. Both students and instructors showed an increase in the level of knowledge regarding microfabricating based on the collected survey results after completing the program. Survey results and observations of participating mentors are presented. 

We report a synthetic strategy to integrate discrete coordination cages into extended porous materials by decorating opposite charges on the singular cage, which offers multidirectional electrostatic forces among cages and leads to a porous supramolecular ionic solid. The resulting material is non-centrosymmetric and affords a piezoelectric coefficient of 8.19 pC N −1 , higher than that of the wurtzite ZnO.