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( 12 ) United States Patent US009748371B2 (12 ) United States Patent ( 10 ) Patent No. : US 9 , 748 ,371 B2 Radosavljevic et al. ( 45 ) Date of Patent : Aug . 29 , 2017 (54 ) TRANSITION METAL DICHALCOGENIDE ( 56 ) References Cited SEMICONDUCTOR ASSEMBLIES ( 71 ) Applicant : Intel Corporation , Santa Clara , CA U . S . PATENT DOCUMENTS (US ) 2007 /0181938 A1 8 /2007 Bucher et al . ( 72 ) Inventors: Marko Radosavljevic , Portland , OR 2009/ 0146141 A1 6 /2009 Song et al. (US ) ; Brian S . Doyle , Portland , OR (Continued ) (US ) ; Ravi Pillarisetty , Portland , OR (US ) ; Niloy Mukherjee , Portland , OR FOREIGN PATENT DOCUMENTS (US ) ; Sansaptak Dasgupta , Hillsboro , OR (US ) ; Han Wui Then , Portland , KR 101348059 B1 1 / 2014 OR (US ) ; Robert S . Chau , Beaverton , WO 2012093360 A1 7 / 2012 OR (US ) ( 73 ) Assignee : INTEL CORPORATION , Santa Clara , OTHER PUBLICATIONS CA (US ) International Search Report and Written Opinion mailed Dec . 11 , ( * ) Notice : Subject to any disclaimer, the term of this 2014 , issued in corresponding International Application No . PCT/ patent is extended or adjusted under 35 US2014 /031496 , 10 pages . U . S . C . 154 (b ) by 0 days . (Continued ) (21 ) Appl. No. : 15 /120 , 496 ( 22 ) PCT Filed : Mar. 21 , 2014 Primary Examiner — Jaehwan Oh (86 ) PCT No .: PCT /US2014 /031496 (74 ) Attorney , Agent, or Firm — Schwabe, Williamson & $ 371 (c ) ( 1 ) , Wyatt , P . C . ( 2 ) Date : Aug . 19 , 2016 ( 87 ) PCT Pub . No . : WO2015 / 142358 (57 ) ABSTRACT PCT Pub . Date : Sep . 24 , 2015 Embodiments of semiconductor assemblies, and related (65 ) Prior Publication Data integrated circuit devices and techniques, are disclosed US 2017 /0012117 A1 Jan . 12 , 2017 herein . In some embodiments , a semiconductor assembly (51 ) Int. CI. may include a flexible substrate , a first barrier formed of a HOIL 29 / 778 ( 2006 . 01 ) first transition metal dichalcogenide ( TMD ) material, a HOIL 29 / 786 transistor channel formed of a second TMD material, and a ( 2006 .01 ) second barrier formed of a third TMD material. The first (Continued ) barrier may be disposed between the transistor channel and (52 ) U . S . CI. the flexible substrate , the transistor channel may be disposed CPC .. HOLL 29/ 7782 ( 2013 .01 ) ; HOLL 21/ 02422 between the second barrier and the first barrier, and a ( 2013 .01 ) ; HOLL 21/ 02568 ( 2013 .01 ) ; bandgap of the transistor channel may be less than a bandgap (Continued ) of the first barrier and less than a bandgap of the second ( 58 ) Field of Classification Search barrier. Other embodiments may be disclosed and /or ??? . .. .. .. HO1L 29 / 24 ; HO1L 29 /66969 ; HOIL claimed . 29 /78696 ; HO1L 21 /02568 ; HOIL 29 /78681 ; H01L 29/ 778 ; H01L 21 /02527 See application file for complete search history . 22 Claims, 6 Drawing Sheets 100 116 118 - - 120 114 12424. .ULU . 106 108 112 110 - 124124 104 102 122 US 9 ,748 ,371 B2 Page 2 (51 ) Int . Cl. HOIL 29 /24 ( 2006 .01 ) HOIL 21/ 02 ( 2006 . 01 ) HOIL 21/ 8256 ( 2006 .01 ) HOIL 27 / 12 ( 2006 .01 ) HOIL 29 /66 ( 2006 . 01 ) HOIL 29 /08 ( 2006 . 01) (52 ) U . S . CI. CPC .. .. .. HOIL 21 /8256 ( 2013 .01 ) ; HOIL 27 / 124 ( 2013 . 01 ) ; HOIL 27 / 1225 ( 2013 .01 ) ; HOIL 29 /24 ( 2013 . 01 ) ; HOIL 29 /66969 ( 2013 .01 ) ; HOIL 29 / 786 ( 2013 . 01 ) ; HOIL 29 /0843 ( 2013 .01 ) ( 56 ) References Cited U . S . PATENT DOCUMENTS 2013 /0105824 A1 5 / 2013 Paranjape et al . 2015 / 0303315 A1 * 10 / 2015 Das .. .. .. .. .. HO1L 29 /78681 257 / 347 2016/ 0093491 A1 * 3 / 2016 Choi . .. .. .. HO1L 21/ 02485 438 / 151 2017/ 0015599 A1 * 1 / 2017 Bessonov .. .. .. .. .. .. .. C04B 41/ 80 OTHER PUBLICATIONS Taiwan Office Action mailed mailed Jul . 26 , 2016 , issued in corresponding Taiwan Patent Application No . 104104565 . International Preliminary Report on Patentability mailed Oct . 6 , 2016 , issued in corresponding International Application No . PCT/ US2014 /031496 , 7 pages. * cited by examiner U . S . Patert A ug. 29, 2017 sheet 1 of 6 US 9 , 748 , 371 B2 ? ?? ?? 6 ? 3 ??. 2 ? # 223 24 ,, . ?? ??? ????????????????????-- - - - -. - - - - - - . 124. # ??????? ? ? 22 FIG. 1 2C - - 202 ?02 EIG. 2 U . S . Patent Aug. 29 , 2017 Sheet 2 of 6 US 9, 748 . 371 B2 32 3 ~ 302 | 104 102 FIG . 3 400 42 | 110 104 102 FIG. 4 112 10 104 02 FIG . 5 U . S . Patent Aug. 29 ,2017 Sheet 3 of 6 US 9 , 748 ,371 B2 60060- - - - - -- 2 604 5?? - 6 “ ????? 112 11 {} & { . 102 FIG . 6 10 “ ? 18 114 16 { 08 112 11 4, 102 FIG . 7 ...U . S . Patent ...Aug. 29, 2017 Sheet... 4 of 6 ...US 9 , 748... , 371. B2 ? 826 ????????????? ???????????? ??? 82 } ??? 6 ? 82 - 84834 NON 84 84 FIG . 8 U . S . Patent Aug . 29, 2017 Sheet 5 of 6 US 9 ,748 , 371 B2 900 mere START DEPOSIT A TMD MATERIAL ON A FLEXIBLE SUBSTRATE TO FORM A FIRST BARRIER 902 DEPOSIT A TMD MATERIAL ON THE FIRST BARRIER TO FORM A TRANSISTOR CHANNEL 904 DEPOSIT A TMD MATERIAL ON THE TRANSISTOR CHANNEL TO FORMA SECOND BARRIER 906 . - .- .- . - . .-. - . - . .-. DEPOSIT TMD MATERIALS TO FORMA TRANSISTOR SOURCE AND DRAIN 908 DEPOSIT TMD MATERIALS TO FORM CONDUCTIVE CONTACTS 910 FORMDV INTERCONNECTS 912 END FIG . 9 U . S . Patent Aug . 29, 2017 Sheet 6 of 6 US 9 ,748 , 371 B2 = CAMERA COMMUNICATION CHIP PROCESSOR 1006 1004 COMMUNICATION CHIP 1006 CHIPSET DRAM DRAM ???? GRAPHICS 2 AMP CPU fram UU ROM 2 TOUCHSCREEN 2 CONTROLLER GPS COMPASS MOTHERBOARD 1002 TOUCHSCREEN SPEAKER DISPLAY BATTERY COMPUTING DEVICE 1000 FIG . 10 US 9 ,748 , 371 B2 TRANSITION METAL DICHALCOGENIDE first transition metal dichalcogenide ( TMD ) material, a SEMICONDUCTOR ASSEMBLIES transistor channel formed of a second TMD material, and a second barrier formed of a third TMD material. The first CROSS -REFERENCE TO RELATED barrier may be disposed between the transistor channel and APPLICATION 5 the flexible substrate , the transistor channel may be disposed between the second barrier and the first barrier , and a The present application is a national phase entry under 35 bandgap of the transistor channelmay be less than a bandgap U . S . C . 8371 of International Application No. PCT/ US2014 ) of the first barrier and less than a bandgap of the second barrier. 031496 , filed Mar . 21 , 2014 , entitled “ TRANSITIONR10 The semiconductor assemblies and related techniques METAL DICHALCOGENIDE SEMICONDUCTOR 10 disclosed herein may enable the formation of transistor ASSEMBLIES , ” which designates the United States of device layers on flexible substrates with improved perfor America , the entire disclosure of which is hereby incorpo mance properties over existing flexible substrate integrated rated by reference in its entirety and all purposes . circuit (IC ) devices. In particular, the semiconductor assem TECHNICAL FIELD 15 blies disclosed herein may use TMD materials , which are compounds of a transition metal and sulfur , selenium , or The present disclosure relates generally to the field of tellurium . TMD materials may take the form of two -dimen semiconductor devices , and more particularly , to semicon sional layers of molecules weakly bonded between layers ductor assemblies with transition metal dichalcogenide via physical bonds ( e . g ., van der Waal' s forces ) to form a 20 three -dimensional structure . In some embodiments , a semi ( TMD ) materials . conductor assembly may predominantly or wholly be BACKGROUND formed of TMD materials . Various embodiments of TMD materials may provide a Some attempts have been made to develop flexible elec - number of advantages over conventional semiconductor tronic circuits for use in wearables and other devices. In 25 materials . First , a conventional three -dimensional material these devices, flexibility has typically been obtained at the may be constrained by strong chemical bonds ( e . g . , covalent expense of electrical performance . In particular, because the around bonds) between molecules in a layer and between substrates used in existing flexible electronic circuits are layers, and therefore must absorb the distortion forces both unable to withstand high processing temperatures, only within a layer and between layers . Thus , such materials may semiconductor materials with low processing temperatures 30 be brittle ; if the chemical bonding constraints are violated , have been used ; because these materials typically have a conventional three - dimensional material may fail . By lower performance than materials with high processing contrast, when a TMD material is physically distorted ( e . g ., temperatures, electrical performance of flexible electronic by bending ) , the two -dimensional layers may readily adjust the weak bonds between layers to respond to the distortion circuits has been limited . 35 ( e . g . , by moving and sliding ) . Consequently , various BRIEF DESCRIPTION OF THE DRAWINGS embodiments of TMD materials may be more resilient to physical distortion , and therefore may be more appropriate Embodiments will be readily understood by the following for use with flexible substrates . detailed description in conjunction with the accompanying Additionally , when conventional three - dimensionalmate drawings . To facilitate this description , like reference 40 rials are thinned so as to reduce the number of layers ( and numerals designate like structural elements . Embodiments consequently , the number of layers of chemical bond con are illustrated by way of example , and not by way of straints ) , the thinning may disrupt the crystal structure of the limitation , in the figures of the accompanying drawings . three -dimensional material and may create dangling bonds . FIG . 1 is cross -sectional view of a semiconductor
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