{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T19:48:58Z","timestamp":1771876138529,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2014,7,30]],"date-time":"2014-07-30T00:00:00Z","timestamp":1406678400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a novel class of miniature fluxgate magnetometers fabricated on a print circuit board (PCB) substrate and electrically connected to each other similar to the current \u201cflip chip\u201d concept in semiconductor package. This sensor is soldered together by reversely flipping a 5 cm \u00d7 3 cm PCB substrate to the other identical one which includes dual magnetic cores, planar pick-up coils, and 3-D excitation coils constructed by planar Cu interconnections patterned on PCB substrates. Principles and analysis of the fluxgate sensor are introduced first, and followed by FEA electromagnetic modeling and simulation for the proposed sensor. Comprehensive characteristic experiments of the miniature fluxgate device exhibit favorable results in terms of sensitivity (or \u201cresponsivity\u201d for magnetometers) and field noise spectrum. The sensor is driven and characterized by employing the improved second-harmonic detection technique that enables linear V-B correlation and responsivity verification. In addition, the double magnitude of responsivity measured under very low frequency (1 Hz) magnetic fields is experimentally demonstrated. As a result, the maximum responsivity of 593 V\/T occurs at 50 kHz of excitation frequency with the second harmonic wave of excitation; however, the minimum magnetic field noise is found to be 0.05 nT\/Hz1\/2 at 1 Hz under the same excitation. In comparison with other miniature planar fluxgates published to date, the fluxgate magnetic sensor with flip chip configuration offers advances in both device functionality and fabrication simplicity. More importantly, the novel design can be further extended to a silicon-based micro-fluxgate chip manufactured by emerging CMOS-MEMS technologies, thus enriching its potential range of applications in modern engineering and the consumer electronics market.<\/jats:p>","DOI":"10.3390\/s140813815","type":"journal-article","created":{"date-parts":[[2014,7,30]],"date-time":"2014-07-30T09:19:07Z","timestamp":1406711947000},"page":"13815-13829","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":46,"title":["High-Sensitivity Low-Noise Miniature Fluxgate Magnetometers Using a Flip Chip Conceptual Design"],"prefix":"10.3390","volume":"14","author":[{"given":"Chih-Cheng","family":"Lu","sequence":"first","affiliation":[{"name":"Institute of Mechatronic Engineering, National Taipei University of Technology, Taipei 10608, Taiwan"},{"name":"Department of Mechanical Engineering, National Taipei University of Technology,  Taipei 10608, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jeff","family":"Huang","sequence":"additional","affiliation":[{"name":"Institute of Mechatronic Engineering, National Taipei University of Technology, Taipei 10608, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Po-Kai","family":"Chiu","sequence":"additional","affiliation":[{"name":"Institute of Mechatronic Engineering, National Taipei University of Technology, Taipei 10608, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shih-Liang","family":"Chiu","sequence":"additional","affiliation":[{"name":"Institute of Mechatronic Engineering, National Taipei University of Technology, Taipei 10608, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jen-Tzong","family":"Jeng","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung 80778, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2014,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/S0924-4247(03)00094-3","article-title":"Advances in fluxgate sensors","volume":"106","author":"Ripka","year":"2003","journal-title":"Sens. Actuators A Phys."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1108","DOI":"10.1109\/JSEN.2010.2043429","article-title":"Advances in magnetic field sensors","volume":"10","author":"Ripka","year":"2010","journal-title":"IEEE Sens. J."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"376","DOI":"10.1109\/TMAG.1970.1066795","article-title":"The fluxgate mechanism, part I: The gating curves of parallel and orthogonal fluxgates","volume":"6","author":"Primdahl","year":"1970","journal-title":"IEEE Trans. Magn."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3678","DOI":"10.1063\/1.1149158","article-title":"Signal-to-noise improvement of bio-magnetic signals using a flux-gate probe and real time signal processing","volume":"69","author":"Dolabdjian","year":"1998","journal-title":"Rev. Sci. Instrum."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"236","DOI":"10.1016\/j.sna.2003.09.014","article-title":"Single core fully integrated CMOS micro-fiuxgate magnetometer","volume":"110","author":"Kejik","year":"2004","journal-title":"Sens. Actuators A Phys."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"236","DOI":"10.1016\/j.sna.2006.02.004","article-title":"Noise spectrum of pulse excited fluxgate sensor","volume":"132","author":"Kubik","year":"2006","journal-title":"Sens. Actuators A Phys."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"3696","DOI":"10.1109\/TMAG.2012.2204237","article-title":"Enhancement in sensitivity using multiple harmonics for miniature fluxgates","volume":"48","author":"Jeng","year":"2012","journal-title":"IEEE Trans. Magn."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"752","DOI":"10.1016\/j.ics.2005.03.164","article-title":"Magnetic Navigation System for Thoracoscopic Surgery of the Pig Lung Partial Resection with Transbronchial Marking","volume":"1281","author":"Shimada","year":"2005","journal-title":"Int. Congr. Ser."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1859","DOI":"10.3390\/s100301859","article-title":"Small fluxgate magnetometers: Development and future trends in Spain","volume":"10","author":"David","year":"2010","journal-title":"Sensors"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"7785","DOI":"10.3390\/s91007785","article-title":"Resonant magnetic field sensors fased on MEMS technology","volume":"9","author":"Manjarrez","year":"2009","journal-title":"Sensors"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"225","DOI":"10.1016\/S0924-4247(99)00034-5","article-title":"AC-driven AMR and GMR magnetoresistors","volume":"76","author":"Ripka","year":"1999","journal-title":"Sens. Actuators A Phys."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"07E912","DOI":"10.1063\/1.2838017","article-title":"Magnetic giant magnetoresistance commercial off the shelf for space applications","volume":"103","author":"Michelena","year":"2008","journal-title":"J. Appl. Phys."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"8382","DOI":"10.1063\/1.1555975","article-title":"Chopping techniques for low-frequency nanotesla spin-dependent tunneling field sensors","volume":"93","author":"Jander","year":"2003","journal-title":"J. Appl. Phys."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"916","DOI":"10.1109\/JSEN.2004.841451","article-title":"High-sensitivity giant magneto-inductive magnetometer characterization implemented with a low-frequency magnetic noise-reduction technique","volume":"5","author":"Boukhenoufa","year":"2005","journal-title":"IEEE Sens. J."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"174","DOI":"10.1016\/S0924-4247(99)00360-X","article-title":"CMOS planar 2D micro-fluxgate sensor","volume":"82","author":"Chiesi","year":"2000","journal-title":"Sens. Actuators A Phys."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"208","DOI":"10.1016\/j.sna.2003.08.015","article-title":"Planar fluxgate sensor with an electrodeposited amorphous core","volume":"109","author":"Perez","year":"2004","journal-title":"Sens. Actuators A Phys."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1109\/TIM.2006.887218","article-title":"A fluxgate magnetic sensor: From PCB to micro-integrated technology","volume":"56","author":"Baschirotto","year":"2007","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1016\/j.sna.2008.01.018","article-title":"Microfluxgate sensors for high frequency and low power applications","volume":"145\u2013146","author":"Delevoye","year":"2008","journal-title":"Sens. Actuators A Phys."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"787","DOI":"10.1007\/s00542-009-0985-0","article-title":"MEMS fluxgate magnetometer for parallel robot application","volume":"16","author":"Kirchhoff","year":"2010","journal-title":"Microsyst. Technol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"969","DOI":"10.1007\/s00542-009-0847-9","article-title":"MEMS micro fluxgate sensors with mutual vertical excitation coils and detection coils","volume":"15","author":"Lei","year":"2009","journal-title":"Microsyst. Technol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"3752","DOI":"10.1109\/TMAG.2011.2158409","article-title":"Design, fabrication and characterisation of a 3D CMOS Fluxgate Magnetometer","volume":"47","author":"Lu","year":"2011","journal-title":"IEEE Trans. Magn."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1016\/j.sna.2012.03.008","article-title":"Responsivity and noise of a wire-bonded CMOS micro-fluxgate sensor","volume":"179","author":"Lu","year":"2012","journal-title":"Sens. Actuators A Phys."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1016\/j.sna.2010.02.014","article-title":"A closed core microfluxgate sensor with cascaded planar FeNi rings","volume":"162","author":"Zorlu","year":"2010","journal-title":"Sens. Actuators A Phys."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"286","DOI":"10.1016\/j.sna.2004.03.061","article-title":"PCB technology used in fluxgate sensor construction","volume":"115","author":"Tipek","year":"2004","journal-title":"Sens. Actuators A Phys."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1109\/JSEN.2006.886998","article-title":"Ka\u030cspar, P. Low-power printed circuit board fluxgate sensor","volume":"7","author":"Pavel","year":"2007","journal-title":"IEEE Sens. J."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/8\/13815\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:14:12Z","timestamp":1760217252000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/8\/13815"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,7,30]]},"references-count":25,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2014,8]]}},"alternative-id":["s140813815"],"URL":"https:\/\/doi.org\/10.3390\/s140813815","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,7,30]]}}}