| US 7,556,979 B2 | ||
| Negative thermal expansion system (NTEs) device for TCE compensation in elastomer composites and conductive elastomer interconnects in microelectronic packaging | ||
| Gareth Geoffrey Hougham, Ossining, N.Y. (US); S. Jay Chey, Ossining, N.Y. (US); James Patrick Doyle, Bronx, N.Y. (US); Xiao Hu Liu, Croton On Hudson, N.Y. (US); Christopher V. Jahnes, Upper Saddle River, N.J. (US); Paul Alfred Lauro, Brewster, N.Y. (US); Nancy C. LaBianca, Yalesville, Conn. (US); and Michael J. Rooks, Briarcliff Manor, N.Y. (US) | ||
| Assigned to International Business Machines Corporation, Armonk, N.Y. (US) | ||
| Filed on Oct. 31, 2007, as Appl. No. 11/932,385. | ||
| Application 11/932385 is a division of application No. 10/310532, filed on Dec. 05, 2002, granted, now 7,417,315. | ||
| Prior Publication US 2008/0048305 A1, Feb. 28, 2008 | ||
| Int. Cl. H01L 21/00 (2006.01) | ||
| U.S. Cl. 438—53 [257/E21.254; 257/E27.008] | 7 Claims |
| 1. A method for fabricating a negative thermal expanding system device, comprising the steps of:
heating a substrate to a desired reference temperature;
depositing a blanket of an organic release layer onto the substrate;
depositing a first layer of material onto the organic released layer;
depositing a second layer of material having a greater TCE value than the first layer of material;
depositing a decomposable polymer layer onto the second layer of material;
patterning the decomposable polymer layer into disk shapes with finger-like appendages radiating from the disk;
depositing a third layer of material having the same TCE value as the second layer of material over the decomposable polymer
layer;
depositing a fourth layer of material having the same TCE value as the first layer of material onto the third layer material;
depositing a layer of photoresist onto the fourth layer material;
lithographically patterning such that the disk shapes of resist are left covering the decomposable polymer disks buried below
and orienting the photoresist layer concentrically;
etching through an exposed area of all layers of material and the organic release layer the until the silicon substrate is
encountered on the bottom;
removing the photoresist layer;
releasing a structure from the substrate; and
annealing thermally to decompose the polymer core to form the negative thermal expansion system device.
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