A new method to integrate fluidic access to devices made by surface channel technology is proposed. The method uses a high aspect-ratio DRIE process for etching wafer through trenches to allow access to the front side of the surface channel device. LPCVD of TEOS is used as etch-stop and to define a reliable connection between channel and access trench during fabrication. The resulting connection is robust and increases design freedom for the surface channel technology. The complete fluid path has only one wetting material

de Boer, Meint J.

Groenesteijn, Jarno

Lammerink, Theodorus S.J.

Lötters, Joost Conrad

Wiegerink, Remco J.

English

NARCIS 

Wafer-through access trenches for surface channel technology

University of Twente Research Information

3. Interfa(please ch WJ. G1MES Novelty: fluidic actechnologprocess faccess to LPCVD oreliable cduring faand incretechnologwetted m Previouswas introrange of channels µm can bare freelywith fronrobustnesthe introdmethod pthe front vacuum equipmenproblemsaspect-ratwafer, making thFigure 1 profiles oright undconnectioresult is surface ccase whebottom othe channthe case notching end. Whoverlaps disrupt tchannels.wafer dur Back-sidmore reluniformitchannels,uniformittrenches channels ces  oose categorAFER-TroenesteijnA+ InstitutWe have descess to devy. The methoor etching wthe front sidef TEOS is uonnection betbrication. Thases design fy. The comaterial, allowi work: In [duced as a ufluidic devicwith a diamee made. The c suspended. t-side access s, scalability uction of bacrovided a moside of the dsealing and t. While t, it also intio DRIE etchintroduced e method mashows a schf the DRIE perneath the n to the surfashown in Fihannel overlare the procef the hole is rel: no connewhere the causes the hoen the hole with the etchhe channel  Both etch-pring processine access treiable, more ies and less d two changies are reduceinstead of rare fabricat  y from list)  HROUGH1, M.J. de Be for Nanot2Bronkhorigned a new mices made byd uses a highafer-through  of the surfased as etch-stween channele resulting coreedom for thplete fluid png for high ch1], surface chniversal teches. With the ter of a few µhannels can bThe technoloholes. Problemand fabricatik-side accessre robust conevice open fo(optical) reahis methodroduced new, required towafer-scale inly suitable ematic overrocess with thsurface (top) ce channel (bgure 1a. Thep slightly. Fiss etched slounded and hction is madeprocess etchele to increasebecomes larg-slits for thefabrication, rofiles are obsg. nches: To mtolerant to ependent on tes were md due to the ound holes ed first andPoste(if req ACCESS TEoer1, T.S.Jechnology,st High-Teethod to inte surface ch aspect-ratio Dtrenches to ace channel deop and to def and access trnnection is re surface chath has onlyemical inertnannel technonology for a technology, mm up to overe released sogy was introds with relation freedom l holes in [2].nection and ler post-procesd-out by ext solved se ones. The  etch througnon-uniformfor large chanview of the e channels shand the resuottom). The  access holegure 1b showightly sloweras not yet rea. Figure 1c sd slightly f in diameter ae enough th channels, itesulting in erved on the ake the prwafer-scale he diameter oade. First, use of rectan[3]. Second then the ar  uesting posteTRENCHCHNOLO. Lammerin Universitych BV, Ruugrate annel RIE llow vice. ine a ench obust annel  one ess. logy wide icro  100  they uced on to ed to  This aves sing, ernal veral high h the ities nels. etch-own lting ideal  and s the , the ched hows aster, t the at it  will leaky same ocess non-f the non-gular , the ccess trencmakchantrencoxid(Figutrencpropcan connFigucompprobnon-trencchanchanchanoutliarea imaghoriz Wor Submfor N217,+31-  FiguDRIEBottohole too schannotchincrechanr) ES FOR SUGY k1, J.C. Löt of Twente,rlo, The Nhes as showes sure that nel fabricatioh etch, a laye is depositedre 2b). Thish etch and erly defined. completely oection betwere 3. It alsolete height lem, allowinuniformities. h successfullnels. Figure nels are darknel are still ned by the doinside the ches of crossontal red lined Count: 600itting authoanotechnolo7500 AE E53-4894373, re 1: Schema process. m: top-viewand surface hort: the accnel, no conning causes ase. When itnel fabricatio    RFACE Cters1,2 and R Enschede, etherlands n in the outthe trench n. To protect er of tetraeth inside the c functions amakes sure Due to this lverlap with then channel an allows for of the chang for compenFigure 4 showy connected 4a shows a red. The etcvisible as datted line and annels. Figur-sections alos respectively r: J. Groenegy, Universitynschede, The-mail: j.groetic overview Top: cross-sof the connchannel. A) ess hole doesection is madthe diameter  increases ton resulting in HANNEL.J. WiegerThe Netherline in Figurcannot interthe channels ylorthosilicathannels usings an etch-stothat the connayer, the acce channel, ed trench as an over-etchnel before csation of ws images of to five parall top view. h-slits used trk dots. The can be seen ae 4b and c shng the ver in Figure 4asteijn, MESA of Twente, e Netherlandnesteijn@utwof a high asection of thection betweideal result.  not reach the. C) etched of the acceso much, it w leaky channe ink1 lands e 2. This fere with during the e (TEOS)  LPCVD p for the ection is ess trench nsuring a shown in  for the ausing a afer-scale an access el surface The five o etch the trench is s a darker ow SEM tical and . + Institute P.O. Box s, phone: ente.nl.  pect-ratio e wafer. en access B) etched e surface too long: s hole to ill disrupt ls Figure 2.back-sidefabricatioDRIE.  Cthe channFigure 3.trenches. proper coFigure 4between channels by the dathe surfalocations  Figure 4between svertical rchannels, Schematic vi access trn. B) TEOS ) TEOS remels and form  Top-view of The trench cnnection. a. Photograpaccess trencwith a cross-shed line andce channelsof the cross-sb. SEM imaurface channed line in fig ensuring thaew of the fabenches. A) LPCVD andoval and SiRthe channel wthe design forosses the chh of a succh and five channel. The can be seen a. The red lections in Figge of a succel and accesure 4a. The t is always ‘hrication procesurface cha high aspect-N LPCVD toall.  r back-side aannel, ensuressful conneparallel su trench is outs a darker arines indicateure 4. essful connes trench alontrench crosseits’ the chann ss of nnel ratio  seal ccess ing a  ction rface lined ea in  the  ction g the s the el.  Figubetwtrencfive left adue tREF [1] MLam“A vapplMicr[2] JR.J. withtro M22ndjan. 2[3] HLouwmethplasmdepthprocequipMicrre 4c. SEM een five parah along the channels are t the top, alo wafer-scaleERENCE. Dijkstra, Mmerink, R.J. ersatile surfaications.”, Joengineering. Haneveld, TWiegerink, “M integrated caechanical Sy Internationa009 .V. Jansen, Merse and Mod x: a reva etching of comparisonesses as ament”, Jouoengineeringimage of a llel surface chorizontal redconnected whlowing for o non-uniformS: .J. De Boer, JWiegerink ace channel coournal of , 17:1971, 200.S.J. Lammericro coriolispacitive readostems, 2009. Ml Conference .J. De Boer, .C. Elwensiew on high silicon with between bo roadmap rnal of M, 19:033001, 2successful channels and  line in figuile there is sver-etching ifities. .W. Berenschnd M.C. Elwncept for miMicromechan7. ink, M.J. de B mass flow seut”,Micro ElEMS 2009. on, pages 463S. Unnikrishnpoek, “Blac speed and  profile contrsch and cryto next gicromechan009.  onnection an access re 4a. All till silicon  required ot, T.S.J. enspoek, crofluidic ics and oer and nsor ec- IEEE  –466, an, M.C. k silicon selective ol: an in-ostat drie eneration ics and 

Wafer-through access trenches for surface channel technology

Abstract

Similar works

Full text

Available Versions

NARCIS

University of Twente Research Information