The three-dimensional quadrupole ion trap (QIT) is an extraordinary device. It functions both as an ion store in which gaseous ions can be confined for a period of time and as a mass spectrometer of considerable mass range and variable mass resolution. Over the past few decades, it has evolved into a powerful tool for both research and routine analysis. The basic objective of this thesis is the development of a three-dimensional quadrupole ion trap with cylindrical symmetry in laminar approximation. The laminar construction allows hyperbolic geometry to be well approximated with minimal construction effort and also provides more access into the trap through interlaminar spaces without disruption of the field. The performance of the trap is examined in the mass selective trapping mode and mass-selective instability mode. Fourier detection is also done. Resolution of our instrument is limited by the external hardware. There is not good enough data quality and so not a good enough spectrum to predict its resolution accurately. A few changes to the instrumentation of the trap will improve the resolution.

Mass spectrometry is a technique that analyzes the chemical compositions of compounds based on the mass-to-charge ratio of their ionized constituents. Miniaturized ion trap mass spectrometry finds application in a wide range of fields where portable, rugged, and reliable analytical instruments are required. Ion traps of various designs have been introduced over the past decades, each with their own unique advantages and capabilities. However, the process of developing a novel miniaturized ion trap mass spectrometer continues to be fraught with challenges. This dissertation discusses simulation studies pertaining to the development of a novel dual ion trap, the simplified coaxial ion trap, consisting of a simplified toroidal ion trap and a cylindrical ion trap. Ions are initially trapped in the toroidal region and the target ions are transferred to the cylindrical region where they are fragmented and mass analyzed, while the rest of the ion population remains securely trapped in the toroidal region. The compact design and extended trapping volume secure several advantages that are not available to conventional ion trap designs. The simulations were geared towards the determination of an optimized geometry and optimal operating conditions for the simplified coaxial ion trap. Four main criteria were used in the determination of the ideal geometric and operating conditions; namely, mass-selectivity of transfer from the toroidal to cylindrical traps, transfer and trapping efficiency in the cylindrical ion trap, mass resolution, and unidirectional ejection. The optimized geometry demonstrates successful trapping of ions in the toroidal region and selective transfer of target ions to the cylindrical region. Unidirectional inward ejection of ions could be achieved with a positive hexapole component in the electric field. The mass resolution under optimized conditions of the toroidal trap was 0.3 Da (FWHM), which agrees with the experimental value. The simplified coaxial ion trap yielded a total transfer and trapping efficiency of 25%. A number of suggestions to improve the efficiency are also discussed as part of this work.

Radio frequency (RF) ion traps based on the quadrupole device developed by Paul and Steinwedel utilize a dynamic electric field to spatially confine the trajectory of charged particles and may be employed as mass spectrometers by selectively ejecting trapped molecules based on the mass to charge ratio. Because of the inherent sensitivity and specificity of this process, ion trap mass spectrometers have become a popular scientific instrument. In the past two decades there has been a push to develop portable ion trap mass spectrometers for in situ mass analysis by geometrically scaling traps to smaller sizes. This decreases the power and vacuum requirements which allows field portable instruments to use smaller/less powerful vacuum pumps and batteries. This dissertation presents the process of miniaturizing the planar linear ion trap (PLIT) to a microscale radius in order to investigate the scaling limits of mass spectrometers. The ultimate end goal is the integration of a PLIT into a portable mass spectrometry system. The PLIT consists of two flat, non-conducting plates, on which fine metal electrodes are patterned using standard microfabrication processes, including photolithography. An RF field is distributed across the electrodes to create a quadrupole electromagnetic potential which traps ions based on their mass to charge ratio. While simple in concept, the PLIT has been developed over a ten-year period including an investigation of a variety of substrate materials and design geometries. This dissertation briefly reviews the optimal fabrication flow and why the stated parameters have advantages over other possible combinations in a coplanar ion trap. Since ion trap miniaturization reduces the trapping volume (which also worsens the SNR and resolution of a mass spectrum), a novel RF phase tracking circuit was developed to exploit a phase locked condition during double resonance ejection. This was implemented on the PLIT to increase SNR before constructing the µPLIT. Better than unit resolutions (0.5 Da, FWHM) and SNR improvements were observed.Lastly, the successful miniaturization of the PLIT to a microscale radius is presented. This was done by redesigning the electrodes on the PLIT surface to have an equivalent trap radius (ro) of 800 μm. The μPLIT successfully confined then resonantly ejected ions with resolutions of approximately 2-3 Da. The performance of the μPLIT was also tested over a range of pressures from 2.5-42×10-3 Torr and retained resolutions between 2.3-2.7 Da. Ultimately, the μPLIT was shown to retain resolutions viable for portable mass spectrometry at pressures in the tens of millitorr while consuming a factor of 3.38 less power than the unscaled PLIT.

New ion trap mass spectrometry (ITMS) instrumentation, the toroidal IT and halo IT, were developed to meet the significant growth in on-site analysis applications. The miniature toroidal IT mass analyzer was operated with radio frequency (RF) trapping voltages of 3 kVp-p or less. Despite its reduced dimensions, it has roughly the same ion trapping capacity as conventional 3D quadrupole ITs. Unit-mass resolved spectra for n-butylbenzene, xenon, and naphthalene were obtained. The desired linear mass scale was obtained using conventional mass-selective instability scan combined with resonance ejection. The halo IT was also based on toroidal trapping geometry and microfabrication technology, consisting of two parallel ceramic plates, the facing surfaces of which were imprinted with sets of concentric ring electrodes. Unlike conventional ITs, in which hyperbolic metal electrodes establish equipotential boundary conditions, electric fields in the halo IT were established by applying different RF potentials to each ring. The potential on each ring could be independently optimized to provide the best trapping field. The halo IT featured an open structure, allowing easy access for in situ ionization. The toroidal geometry provided a large trapping volume. The photolithographic fabrication method avoided difficulty in meeting the required machining tolerances. Preliminary mass spectra showed resolution (m/δ m) of 60–75 when the trap was operated at 1.9 MHz and 500 Vp-p. Ion ejection through a hole in the center of the trap, and through slits machined in the ceramic plates were evaluated. The latter ejection method was done to mimic the design of the toroidal IT. The preferred electric fields containing higher order components were optimized by adjusting the potentials applied to the electrode rings of the halo IT without changing the original trapping plates and structure of the IT. The performance of the halo IT with 1% to 7% octopole field (A4/A2) components was determined. A best resolution of 280 (m/δ m) was obtained with 5% octopole field. SIMION simulations were used to demonstrate the toroidal trapping of ions and their mass analysis in both toroidal and halo ITs.

A new approach of making ion trap mass analyzers was developed in which trapping fields are created in the space between two ceramic plates. Based on microfabrication technology, a series of independently-adjustable electrode rings is lithographically patterned on the facing surfaces of each ceramic plate. The trapping field can be modified or fine-tuned simply by changing the RF amplitude applied to each electrode ring. By adjusting the potential function applied to the plates, arbitrary trapping fields can be created using the same set of ceramic plates. Unlike conventional ion traps, the electrodes of planar ion traps have a non-equipotential surface, thus the electric field is independent of electrode geometry and can be optimized electronically. The simple geometry and open structure of planar ion traps address obstacles to miniaturization, such as fabrication tolerances, surface smoothness, electrode alignment, limited access for ionization or ion injection, and small trapping volume, thereby offering a great opportunity for a portable mass spectrometer device. Planar ion traps including the planar quadrupole ion trap and the coaxial ion trap have been designed and tested using this novel method. The planar quadrupole trap has demonstrated a mass range up to 180 Da (Th), with mass resolution typically between 400-700. We have also developed a novel ion trap in which both toroidal and quadrupolar trapping regions are created simultaneously between a set of plates. This "Coaxial Trap" allows trapping and mass analysis of ions in two different regions: ions can be trapped and mass analyzed in either the toroidal or quadrupolar regions, and transferred between these regions. Some simulation work based on the ion motion between two different trapping regions in the coaxial ion trap has been performed. Using a one-dimensional simulation method, ion motion was investigated to transfer ions between these two regions. The effect of the mutipole components in the radial field and axial field, amplitude and frequency of the primary RF and supplementary AC signal were studied to obtain high mass resolution in the axial direction and high transfer efficiency in the radial direction. In all these devices, the independent control of each patterned electrode element allows independent control of higher-order multipole fields. Fields can be optimized and changed electronically instead of physically as is done in conventional traps.

This dissertation presents advances in the development of planar electrode ion traps. An ion trap is a device that can be used in mass analysis applications. Electrode surfaces create an electric field profile that trap ionized molecules of an analyte. The electric fields can then be manipulated to mass-selectively eject ions out of the trap into a detector. The resulting data can be used to analyze molecular structure and composition of an unknown compound. Conventional ion traps require machined electrode surfaces to form the electric trapping field. This class of electrode presents significant obstacles when attempting to miniaturize ion traps to create portable mass spectrometers. Machined electrodes lose required precision in shape, smoothness, and alignment as trapping dimensions decrease. Simplified electrode geometries are essential to open the way to miniaturized ion traps. The planar electrode ion trap presents a simplified geometry that utilizes photolithography processes in its fabrication. Patterns of electrodes are patterned on a planar ceramic substrate. Electric fields generated by these patterns can be nearly identical to those of ideal ion traps. The microfabrication processes involve the challenge of patterning on ceramic, patterning on two sides of a substrate, and patterning on a substrate with high topographic features. Four successful designs of planar ion traps are presented in this work: the planar Paul, toroidal, coaxial, and linear ion trap. These four designs have different strengths and weaknesses. The planar Paul trap is simpler to design and operate, the toroidal has a larger ion storage volume and so can be a more sensitive instrument, and the coaxial trap is a hybrid planar Paul and toroidal trap. The linear trap combines the simplicity of the planar Paul trap with the increased storage capacity of the toroidal trap. This work presents how these four designs advance work in miniaturized ion traps. In addition, microfabrication techniques and trap performance for these designs are presented.

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The new ion guide isotope separator, IGISOL--4, at JYFL, Jyvaskyla has been commissioned, and new spectroscopy and structural measurements are reported here. The first optical measurements of radioactive (101,107)Mo isotopes, with definite spin assignments, are presented. The measurements provide insight into the development of the structure and deformation around N=60 for molybdenum. A clear, exaggerated odd--even staggering in the mean--square charge radii up to N=60, followed by an immediate change in character, shows the chain to possess a far less smooth shape development than previously thought. The measurements of 107Mo confirm this isotope to mark the peak of the deformation in molybdenum and these results, achieved in the limits of fission fragment production, display the improved capabilities of the IGISOL--4 facility (these two isotopes were too challenging to be studied previously at IGISOL--3).The commissioning stages of the electrostatic ConeTrap are detailed, from the initial off--line investigations (in comparison to detailed simulations), to the first successfully stored and extracted radioactive ions. The detection of a hyperfine resonance has been achieved from (stable) hafnium ions stored and extracted from the trap prior to resonant excitation, with no observable ion energy perturbations induced by the trapping. The observation of a resonant optical pumping effect on yttrium ion survival is presented. Pumping of an ionic ensemble within the Cooler--Buncher is shown to lead to a change in ion survival, directly observed through a change in the measured ion rates. The ConeTrap was observed to enhance this effect upon further storage of pre--pumped ions. A new, bespoke data acquisition system for collinear laser spectroscopy is presented. The microcontroller based system provides time stamping of photon arrival, a multiple photon tracker for two photon gating and full software control over photon time gates. A novel approach for searching for weak hyperfine peaks is implemented in the system. This `photon multiplication method' provides greater statistics on resonance peaks, providing a greatly increased accuracy in peak centroid determination.

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