Abstract:
A method of forming a layer of silicon on a surface of a substrate (10) comprises the steps of depositing silicon on the surface by a physical deposition process such as electron beam evaporation using a silicon source (4) and, during said deposition process, subjecting the forming film to ionic bombardment from an ion gun (20). The resultant silicon film has stresses which are considerably reduced compared to a film produced by an ordinary physical deposition process. This method is particularly well adapted to the formation of relatively thick silicon layers (≥lνm) on a layer (or stack of layers) of silica, to serve as an etching mask in a subsequent deep etching of the silica by reactive ion etching.
Abstract:
An optical component comprising one or more optical elements (35') aligned with the end(s) of one or more waveguides (25') is fabricated by a process in which, first of all, a doped silica core layer (20) is deposited on a substrate (10) (or on a buffer layer on the substrate), and subsequently a partial overclad layer (30A) typically 1-5 mu m thick is deposited on the core layer. The partial overclad layer and core layer are patterned and etched so as simultaneously to define the optical element(s) and the waveguide core(s). Afterwards, the overclad is completed by depositing a further overclad layer (30B). In the case of application of this fabrication method to a grating-based NBWDM device, the metallisation of the grating can precede or follow the deposition of the second overclad portion (30B). In either case, low-temperature deposition processes are required for deposition of this second overclad portion.
Abstract:
Phosphate free, Er/Yb co-doped borosilicate glass compositions and optical devices made from said compositions are disclosed; said compositions comprising, for 100 parts by weight of: 60 to 70 parts by weight SiO2 or SiO2 + GeO2 with SiO2 always being greater than 40 parts by weight, 8 to 12 parts by weight of B2O3, 10 to 25 parts by weight M2O wherein M2O is an alkali metal oxide, 0 to 3 parts by weight of BaO, 0.1 to 5 parts by weight Er2O3, and from 0.1 to 12 parts by weight of Yb2O3 and from 0 to less than 5 parts by weight F; and within which, the boron atoms are of tetrahedral spatial coordination.
Abstract:
A method of forming a layer of silicon on a surface of a substrate (10) comprises the steps of depositing silicon on the surface by a physical deposition process such as electron beam evaporation using a silicon source (4) and, during said deposition process, subjecting the forming film to ionic bombardment from an ion gun (20). The resultant silicon film has stresses which are considerably reduced compared to a film produced by an ordinary physical deposition process. This method is particularly well adapted to the formation of relatively thick silicon layers (l.mu.m) on a layer (or stack of layers) of silica, to serve as an etching mask in a subsequent deep etching of the silica by reactive ion etching.
Abstract:
Phosphate free, Er/Yb co-doped borosilicate glass compositions and optical devices made from said compositions are disclosed; said compositions comprising, for 100 parts by weight of: 60 to 70 parts by weight SiO2 or SiO2 + GeO2 with SiO2 always being greater than 40 parts by weight, 8 to 12 parts by weight of B2O3, 10 to 25 parts by weight M2O wherein M2O is an alkali metal oxide, 0 to 3 parts by weight of BaO, 0.1 to 5 parts by weight Er2O3, and from 0.1 to 12 parts by weight of Yb2O3 and from 0 to less than 5 parts by weight F; and within which, the boron atoms are of tetrahedral spatial coordination.
Abstract:
A process for the production of an integrated optical circuit in a glass body by ion exchange between certain regions of the glass body and a metallic salt with the use of a mask defining the regions where the ion exchange occurs, characterized in that the mask comprises a layer of silicon.
Abstract:
A process for the production of an integrated optical circuit in a glass body by ion exchange between certain regions of the glass body and a metallic salt with the use of a mask defining the regions where the ion exchange occurs, characterized in that the mask comprises a layer of silicon.
Abstract:
A process for the production of an integrated optical circuit in a glass body by ion exchange between certain regions of the glass body and a metallic salt with the use of a mask defining the regions where the ion exchange occurs, characterized in that the mask comprises a layer of silicon.