Various electromagnetically useful materials have been applied epitaxially to biaxially textured support materials. An important class of substrates is known as rolling assisted, biaxially textured substrates (RABiTS). Biaxial texture in a substrate refers to situation when all the grains in a polycrystalline substrate are aligned within a certain angular range with respect to one another. A polycrystalline material having biaxial texture of sufficient quality for electromagnetic applications can be generally defined as being characterized by an x-ray diffraction phi scan peak of no more than 20° full-width-half-maximum (FWHM) and a omega-scan of 10° FWHM. The X-ray phi-scan and omega-scan measure the degree of in-plane and out-of-plane texture respectively. An example of biaxial texture is the cube texture with orientation {100}<100>, wherein the (100) crystallographic plane of all grains is parallel to the substrate surface and the [100] crystallographic direction is aligned along the substrate length. Other suitable definitions have also been set forth in varying terms.
It is helpful to review some of the prior work that the present invention builds upon. The entire disclosure of each of the following U.S. patents is incorporated herein by reference:    U.S. Pat. No. 5,739,086 issued on Apr. 14, 1998 to Goyal, et al.    U.S. Pat. No. 5,964,966 issued on Oct. 12, 1999 to Goyal, et al.    U.S. Pat. No. 5,968,877 issued on Oct. 19, 1999 to Budai, et al.    U.S. Pat. No. 5,972,847 issued on Oct. 26, 1999 to Feenstra, et al.    U.S. Pat. No. 6,077,344 issued on Jun. 20, 2000 to Shoup, et al.    U.S. Pat. No. 6,114,287 issued on Sep. 5, 2000 to Lee, et al.    U.S. Pat. No. 6,150,034 issued on Nov. 21, 2000 to Paranthaman, et al.    U.S. Pat. No. 6,159,610 issued on Dec. 12, 2000 to Paranthaman, et al.    U.S. Pat. No. 6,180,570 issued on Jan. 30, 2001 to Goyal.    U.S. Pat. No. 6,256,521 issued on Jul. 3, 2001 to Lee, et al.    U.S. Pat. No. 6,261,704 issued on Jul. 17, 2001 to Paranthaman, et al.    U.S. Pat. No. 6,270,908 issued on Aug. 7, 2001 to Williams, et al.    U.S. Pat. No. 6,331,199 issued on Dec. 18, 2001 to Goyal, et al.    U.S. Pat. No. 6,440,211 issued on Aug. 27, 2002 to Beach, et al.    U.S. Pat. No. 6,447,714 issued on Sep. 10, 2002 to Goyal, et al.    U.S. Pat. No. 6,451,450 issued on Sep. 17, 2002 to Goyal, et al.    U.S. Pat. No. 6,617,283 issued on Sep. 9, 2003 to Paranthaman, et al.    U.S. Pat. No. 6,645,313 issued on Nov. 11, 2003 to Goyal, et al.    U.S. Pat. No. 6,670,308 issued on Dec. 30, 2003 to Goyal.    U.S. Patent Application Publication No. 20030143438 published on Jul. 31, 2003 to Norton, et al.    U.S. patent application Ser. No. 10/324,883 filed on Dec. 19, 2002.    U.S. patent application Ser. No. 10/620,251 filed on Jul. 14, 2003.    U.S. Pat. No. 6,632,539 issued on Oct. 19, 2003 to Iijima et al.    U.S. Pat. No. 6,214,772 issued on Apr. 10, 2001 to Iijima et al.,    U.S. Pat. No. 5,650,378 issued on Jul. 22, 1997 to Iijima et al.    U.S. Pat. No. 5,872,080 issued on Feb. 19, 1999 to Arendt et al.    U.S. Pat. No. 6,190,752 issued on Feb. 20, 2001 to Do et al.    U.S. Pat. No. 6,265,353 issued on Jul. 24, 2001 to Kinder et al.    U.S. Pat. No. 5,432,151 issued on Jul. 11, 1995 to Russo et al.    U.S. Pat. No. 6,361,598 issued on Mar. 26, 2002 to Iijima et al.
Moreover, there are other known routes to fabrication of biaxially textured, flexible electromagnetic devices known as ion-beam-assisted deposition (IBAD) and inclined-substrate deposition (ISD). IBAD processes are described in U.S. Pat. Nos. 6,632,539, 6,214,772, 5,650,378, 5,872,080, 5,432,151 and 6,361,598; ISD processes are described in U.S. Pat. Nos. 6,190,752 and 6,265,353; all these patents are incorporated herein by reference. In the IBAD and ISD processes a flexible, polycrystalline, untextured substrate is used and then a biaxially textured layer is deposited on this substrate.
Semiconductor research and development efforts are often focused on increasing the speed of electronic devices. Ultimately, there are only two ways to increase the speed of transistor switches based on existing semiconductor technologies. The first is to reduce the size of the structures on the semiconductor, thereby obtaining smaller transistors that are closer together and use less power. The second is to use alternative semiconductor materials that inherently switch faster. For example, the band-gap effects associated with GaAs's 3:5 valance structure mean that these transistors switch approximately eight times faster and use one-tenth the power of their silicon counterparts. Use of SiC, cubic boron nitride (cBN) and diamond based devices would potentially even faster. Hence, successful fabrication of semiconductors other than Si using industrially scalable routes if of great interest.
It has recently been demonstrated that epitaxy of diamond films can be obtained on Ir surfaces. M. Schreck et al. have shown that single-crystal Ir films can be deposited by electron beam evaporation on rigid, single crystal SrTiO3 surfaces. However, such a process is limited to substrate selections available—rigid single crystal ceramic substrates such as SrTiO3. Such a process cannot be used to make continuous long lengths or wide area devices since it is limited to the size in which SrTiO3 single crystals can be fabricated. Moreover, SrTiO3 are not flexible. Flexible refers to the ability of the substrate to be bent slightly withour cracking.
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