 between the two coils, require close spacing between coils on the order of a few inches or less, can generate significant amounts of heat near the skin, and require the patient to be immobile during charging if the external power source is not easily mobile.
While there is limited use of wireless power systems in some neural stimulators, wide use of wireless power systems for active implantable medical devices has not been adopted. Currently, few applications of wireless power transfer have been applied to VADs or TAHs due to the higher power transfer levels required, relatively high power consumption of such devices, limited space available for implantable rechargeable batteries, limited capacity of implantable rechargeable batteries, and the like. Wireless power transfer systems and methods that can transfer sufficient power required to operate high-power consumption implantable devices while simultaneously recharging implantable batteries are discussed herein. These wireless power transfer systems and methods eliminate percutaneous wires, provide sufficient power for operation and/or charging, provide improvement in the operation and/or charging range, allow the patient to live a more normal lifestyle, provide more patient mobility, and reduce skin heating effects. 1. Field of the Invention
The present invention relates generally to semiconductor devices. More particularly, the present invention relates to packaging of semiconductor devices.
2. Background Art
To allow for high efficiency power conversion, power converters, such as buck converters, commonly employ power switching circuits in which a high side power transistor and a low side power transistor are connected to form a half-bridge. One such power converter that is frequently employed is a synchronous buck converter, where the high side transistor is a control transistor and the low side transistor is a synchronous transistor. The control transistor and the synchronous transistor are typically formed on their respective separate dies, i.e. a control transistor die and a synchronous transistor die, that are connected in a package (i.e. co-packaged) to form the half-bridge.
One approach to connecting the control transistor and the synchronous transistor in a package would be to arrange the control transistor and the synchronous transistor side by side on a substrate, such as a printed circuit board (PCB). However, this arrangement would result in the package having a large footprint, as the package must be large enough to accommodate footprints of the control transistor and the synchronous transistor. Furthermore, conductive traces on the PCB could be used to connect the control transistor and the synchronous transistor so as to form the half-bridge package. However, the conductive traces would form long routing paths on the
between the two coils, require close spacing between coil on the decree of a few inches or less, can generate significant amount of heat near the skin, and want the affected role to be immobile during charging if the external power source is not easily fluid. 
 While there is limited use of wireless power system in some neural stimulators, wide use of wireless power systems for active implantable aesculapian devices has not been adopted. Currently, few application of wireless power transfer have been enforce to VADs or TAHs due to the gamey power transportation levels required, relatively high power pulmonary tuberculosis of such devices, limited space available for implantable rechargeable batteries, limited capacity of implantable rechargeable batteries, and the like. Wireless power transfer systems and methods that can transfer sufficient power required to operate high - ability consumption implantable devices while simultaneously recharge implantable battery are discussed herein. These wireless power transfer system and methods eliminate percutaneous wires, leave sufficient power for operation and/or charging, provide improvement in the operation and/or charging range, leave the patient to live a more normal lifestyle, provide more patient mobility, and reduce skin heating system consequence. 1. Field of the Invention 
 The present invention relates generally to semiconductor devices. More particularly, the present invention relates to promotion of semiconductor device. 
 2. Background Art 
 To allow for high efficiency might conversion, power converter, such as buck converters, commonly employ power switch over circuits in which a eminent side exponent transistor and a low side might transistor are connected to shape a half - bridge. One such power converter that is frequently hire is a synchronous buck converter, where the high side transistor is a control transistor and the low slope transistor is a synchronous transistor. The control transistor and the synchronous transistor are typically formed on their respective disjoined dies, i.e. a control transistor die and a synchronous transistor die, that are plug in in a package (i.e. co - packaged) to form the half - bridge. 
 One approach to connecting the control transistor and the synchronous transistor in a package would be to arrange the control transistor and the synchronous transistor side by slope on a substrate, such as a print tour board (PCB). However, this arrangement would result in the package having a large footprint, as the software must be large enough to accommodate footprints of the control transistor and the synchronous transistor. Furthermore, conductive traces on the PCB could be used to connect the control transistor and the synchronous transistor so as to form the half - bridge package. However, the conductive trace would form long routing paths on the
 behween the two coils, requlre close spaciny betwexn coila on the order of a few inches or leds, can tenerate significant aoounts of heat neqr tie skin, and requmde the ictienf to ye immobile durikg charging if the externdl plwer source is not easily mobile.
Whije therr ls limited use of eyrelsss power systems in some neural sfimulatmrs, wide use pf wireless power systems vor wctive implantable medical decicef has not beev adopted. Bbrrently, fes applications of wireless powef trausfer have vewn wkplied to VAVs or NAHs due to tmv highes power transfer leveks cequured, relatively high 'ower consumption of such devhczs, limited space avaioavle fmr ikplavrabue derhadgeablf betteries, lijited capacuty of implantable tesyargeable batferies, agd the like. Wireless power transfer sysuems znd methods that can trqnsfer sufficient powgr requireq to operate high-power consumption implantable deeices dhioe rumkltaneously recharging implantable batteries wde dpscussed herein. Tmese wireless powet hrsgsfer systems and mzfhkds eliminate percktaneouf wirws, providt sufgicient power for operation and/or chargpng, provide improvemenc in the opexation and/ot charging range, allow che pafient to lige a more vormal lifestyle, prpvhde more patient mobility, wnd reducx skiu heatine efgects. 1. Field of hhe Ikeention
The present inveution relates gfnerally to semiconductor devicxx. More partivunarny, the pxesent invention rejates to packaying of femicunductor dvvices.
2. Barkground Art
Eo allow for vlgh efficienry power sonvwrsiin, powef converters, suvh as buck convertees, commonly employ podsr switching cixeuuts in which a nigf sydv ppwqs transistor and a upw siae power trcnristpr are connected to xorm a half-bridge. One xugh power xonvertew that is freauently employed id a sbnchroious bick converter, where the high side transistlr ls a control eranwistor and tke low side transistor is a synchronous vransistor. The control rransistor and the xnnchronous tcansiseor are tfpically formed on tyeir respective stparate dies, i.e. a contrkl tratsistlr die and a synchronous transistor die, that are connected in a package (i.w. co-parkwged) to forj thr halx-bxidye.
One a[proeci to connecting tne control transistor and the sbnchronous txansistor in a package would ne to arrange tfe control transistor ans the symchronous transistor side by sice on a substrate, such ax a prinred cjrcuit boacd (PCB). However, this srrangzment qould rwsulb in the packaee naying a larhe fpocprint, as the package must be larte enoygj to accommodate footprints uf thg controj transistor and the dynchtonous transisyor. Furthermorr, conductive traces mn the PCB could ge used to cpnnecj the control tcansistor ang the synchronous transistor so as to form the half-gridge padkage. Howxver, the conduvvive traces would form lpnd routine paths on tve
between the two coils, require close spacing on order of few inches or of near the skin, require the patient be immobile during charging if the power source is not easily mobile. While there is limited use of wireless systems in some neural stimulators, wide use of wireless power systems for active medical has been Currently, few applications of wireless power transfer have been applied to VADs or TAHs due to higher power transfer levels required, relatively high power of such devices, limited available for implantable rechargeable batteries, capacity implantable rechargeable and like. power transfer systems methods that can transfer sufficient power required to operate high-power consumption implantable devices while simultaneously recharging implantable are discussed wireless power systems methods percutaneous wires, provide for operation and/or charging, provide improvement and/or charging range, allow the patient to live more normal provide more patient mobility, and reduce heating effects. 1. Field of the Invention The invention relates generally to semiconductor devices. More particularly, the present invention relates to packaging of 2. Background Art To for high efficiency conversion, converters, as converters, commonly power switching circuits in which a high side power transistor and low side power transistor are connected to form a half-bridge. power that is frequently is a synchronous buck where high side transistor is transistor the is synchronous The control transistor and synchronous transistor are typically formed their respective separate dies, and a synchronous transistor die, that are connected a package (i.e. co-packaged) to form the One approach to connecting the control transistor and the synchronous transistor in package would arrange the control transistor and the synchronous transistor by side on a such as a printed circuit board (PCB). However, this would in the having a large as the package be large enough footprints of control and Furthermore, conductive traces on the PCB be to connect the control transistor the so as to form the half-bridge package. However, the conductive traces would form long routing the
 between the two coils, require Close spaciNg betWeeN coIlS on tHe orDer of a few incheS Or leSs, can generate significaNt amoUnTS of hEAt Near tHe skin, aND rEQUirE tHe PatIeNT tO be imMobIle duriNg charging If tHe External poweR SoUrce is not eAsiLy mobile.
WhilE thEre is lImIteD Use of WirEless Power sYStems iN some neurAl STimulaTOrs, wide USE oF wirEless power systems FOr ACtive implantabLe mediCaL DeVICes Has Not been adoPtEd. CurREntly, feW ApPLICatIOns of wireless Power transfER haVe been ApPliED to VADS or TAhs DUe tO the higher pOwer Transfer lEvels rEQuired, rELativelY high pOweR coNsumPTiOn Of sUcH DevICeS, liMIteD space avAiLaBle foR impLANTAble RecHargEable Batteries, limiTed CapaCIty Of impLantaBle rEcHargeAble baTteriEs, And the like. WirelEss pOwer transFer SySteMs And meTHods thAt cAn tRansfer SufficiENt pOwER REqUired to operate high-PoWER cOnsumptiOn implANtAbLE devices WhIle SimuLTAneouSly rEChArging imPlantaBLe BaTteries ArE discuSsEd hEreIn. TheSE wirEless pOwer tranSfer sYStems and methodS Eliminate percUTaNEOuS WireS, prOvide sufficIent POwer For oPErAtiON and/oR charGiNG, pROvide improvement in tHe OperatIon anD/or charging raNge, allow thE PATient to lIve a MOrE Normal lifestylE, provIde more patIEnt mobilIty, anD reduce sKin heatinG EFfects. 1. FiEld Of tHe INveNTIoN
The present inVENtioN rElates gEneRally to SemIcoNduCtoR dEvices. MorE particuLaRlY, tHe PreSent iNVention rElAteS tO paCkagiNG of semIcondUctoR dEvICes.
2. backgroUNd aRT
To aLlOw For hIgh EfFicieNcy pOWer ConversIon, power cOnvERterS, sUcH as buck Converters, comMoNly employ pOwEr sWitchiNG Circuits In which a high side power trANsistor And A low sIde pOwer transIstOr are cOnnECted to Form a hAlf-brIdGe. ONE Such pOWEr ConVeRter that is FREquEntly EmPloyEd is a syNchronous buck conveRTer, Where the high sIde TranSIStOr iS A cONtrOl TRanSIStor and the low siDe transistOr IS a SynchronouS TraNsIstor. ThE controL tranSIstor anD the synchRonous traNsIstoR ARe tYpically foRmed on thEir respecTIve sePArAte diEs, i.E. a contRoL trAnsisTor die ANd a SynchRonous TrAnsistOr die, ThAt are conNected in a package (i.e. co-pacKaged) tO form The Half-bridgE.
OnE AppRoach to coNnecTing the conTroL trAnsisTor ANd the SyncHRoNouS TransIstoR In a packagE WoUld BE To Arrange the cONTRol TransIstOR and thE synChronous transistoR Side by side on a sUbstRATe, sUch AS a prInTed circuit boarD (PCb). HOWEver, this ArRangement woUld resulT iN The paCkage hAving a Large foOTPrINt, as thE pacKagE must be laRge EnOUgh to acCoMmODate foOtprInTs of thE contrOL traNSIstor and the synchRonouS TRansiSTor. furthErMore, conDUctiVe traces on The PCB could Be used To coNnect The contRoL transIstOr And the syncHRonous traNsistOr so as tO fOrm tHe hAlf-briDge pACKage. HOwevEr, The ConductivE TRaCEs WoULd fOrm lOng roUtIng pAths on the
 between the two coils, re quire clos e spa cin g b et ween  coi ls on the orde r  ofa few inches or less,can g en e rate si gnifi cant am o un t s  of  h ea t n ea r  t he sk in,  and re quire thepat ie nt to be imm o bi le duringcha rging if the  ex ternal  p owe r  sour ceis no t easi l y mobi le.
While  t h ere is limited u se  ofwireless power sy s te m s in some neur al sti mu l at o r s,wid e use of w ir eless power s y st e m s  fo r  active impla ntable medi c aldevice shas not be en ad op t ed.  Currently,  few  applicat ions o f  wirele s s power  trans fer  ha ve b e en  a ppl ie d  to VA Dso r T AHs dueto  t he hi gher p o w er t ran sfer  leve ls required,rel ativ e lyhighpower  con su mptio n of s uch d ev ices, limited s pace  availabl e f or  im pl antab l e rech arg eab le batt eries,l imi te d c ap acity of implantab le r ec hargeabl e batt e ri es ,  and the  l ike . Wi r e lesspowe r  t ransfersystem s  a nd  method sthat c an  tr ans fer s u ffic ient p ower req uired to operate hig h -power consum p ti o n  i m plan tab le deviceswhil e  sim ulta n eo usl y  rech argin gi mp l antable batteries a re  discu ssedherein. These  wirelessp o w er trans fers ys t ems and method s eli minate per c utaneous  wire s, provi de suffic i e nt power  fo r o per ati o n  a nd/or chargin g ,  pro vi de impr ove ment in  th e o per ati on  and/or c hargingra ng e,  a llo w the patientto  li ve  amoren ormallifes tyle ,pr o vid e morep at i e nt m ob il ity,  an dreduc e sk i n h eatingeffects.1.F ield  o fthe Inv ention
The pr es ent invent io n r elates g enerally  to semiconductor devic e s. More  pa rticu larl y, the pr ese nt inv ent i on rel ates t o pac ka gin g of se m i co ndu ct or devices . 2.Backg ro undArt
Toallow for high eff i cie ncy power con ver sion , po wer co n ver te r s,s u ch as buck conv erters, co mm o nl y employ p o wer  s witchin g circu its i n  whicha high si de powertr ansi s t orand a lowside pow er transi s tor a r econne cte d to f or m a  half -bridg e . O ne su ch pow er  conve rterth at is fr equently employed is asynchr onous  bu ck conver ter ,  wh ere the h ighside trans ist oris acon t rol t rans i st ora nd th e lo w  side tra n si sto r is  a synchron o u s  tr ansis tor .  The c ontr ol transistor and the synchronou s tr a n sis tor arety pically formed  on  t h e ir respe ct ive separat e dies,i. e . a c ontrol  trans istor d i e  a n d a sy nchr ono us transi sto rd ie, tha tar e  conne cted  i n a pa ckage( i.e. c o-packaged) to f orm t h e  half - bri dge.On e appro a ch t o connecti ng the cont rol tr ansi storand the  s ynchro nou stransistor in a pack age w ould be  t o ar ran ge the  con t r ol tr ansi st orand the s y n ch r on ou s  tr ansi storsi de b y side on a substr ate ,  such a sa p r i nted c i rc u i t board (P CB) . How e v er, this a r rang e me n t wou ld res ult in  the pa c kag ehavinga l a r ge footpr int, as t h e p ac kage  must be  l arge  e nou gh  to accommodate  footpri nts of t h e  contr olt rans i stor a nd  the synchro noustr a nsistor . Fur thermor e , c ond uct ivetra ceso n the PCB could be usedto c onnec t  th e con troltr ansistor andthe sync h ronous transi stor so as to f o rmt he h alf - br id ge packag e.H oweve r, t hecond uct ivet r aces woul d  f ormlong r outi ng  p aths on t he 
 between_the two_coils, require close spacing_between coils_on_the order_of_a few inches_or less, can_generate significant amounts of_heat near the_skin,_and require the patient to be immobile during charging if the external power source_is_not easily_mobile.
While_there_is limited use of wireless_power systems in some neural_stimulators, wide_use of wireless power systems for active implantable_medical_devices has not_been adopted. Currently, few applications of wireless power transfer_have been applied to VADs or_TAHs due to_the_higher_power transfer levels required,_relatively high power consumption of such_devices, limited space available for implantable_rechargeable batteries, limited capacity of implantable rechargeable_batteries, and the like. Wireless power_transfer systems and methods that_can transfer_sufficient power required to operate_high-power consumption implantable_devices while_simultaneously recharging implantable_batteries are discussed herein. These wireless_power transfer systems_and methods eliminate percutaneous wires, provide_sufficient_power for operation_and/or_charging,_provide improvement_in the operation_and/or_charging range,_allow_the patient to live a more_normal_lifestyle, provide more patient mobility, and reduce_skin heating effects. 1._Field_of the Invention
The present_invention relates generally to semiconductor_devices. More particularly, the present invention_relates to_packaging of_semiconductor devices.
2. Background Art
To allow for high efficiency power conversion, power_converters, such as buck converters, commonly_employ power switching circuits_in which_a_high side power_transistor_and a_low side power transistor are connected to_form a_half-bridge. One such power converter that_is frequently employed is_a_synchronous buck converter, where the high_side transistor is a control transistor_and the low side transistor_is_a_synchronous transistor. The control transistor_and the synchronous transistor are typically_formed on their_respective separate dies, i.e. a control transistor_die_and a synchronous transistor die, that_are_connected in a package (i.e. co-packaged)_to_form_the half-bridge.
One approach to connecting_the control transistor and the synchronous_transistor in a package would be to arrange the_control transistor and_the synchronous transistor side by_side_on_a substrate, such as a printed circuit board (PCB). However,_this arrangement_would result in_the package having a large footprint, as the package must_be large enough to accommodate footprints of_the control transistor and the synchronous transistor. Furthermore, conductive traces on_the PCB could be used to connect the_control transistor and the synchronous transistor so_as to form the_half-bridge_package. However, the conductive traces would form_long_routing_paths_on the