Apparatuses and methods for glass laminates having a controlled coefficient of thermal expansion are disclosed. In C one embodiment, a glass laminate includes a glass core having a core thickness (T.sub.core) and a core coefficient of thermal expansion (CTE.sub.core), a first glass cladding layer and a second glass cladding layer. The first glass cladding layer and the second glass cladding layer are arranged such that the glass core is disposed between the first glass cladding layer and the second glass cladding layer. The first glass cladding layer has a first cladding thickness (T.sub.clad1) and a first clad coefficient of thermal expansion (CTE.sub.clad1), and the second glass cladding layer has a second cladding thickness (T.sub.clad2) and a second clad coefficient of thermal expansion (CTE.sub.clad2). The glass laminate has a laminate coefficient of thermal expansion (CTE.sub.L) within a range of about 35×10.sup.−7/° C. to about 90×10.sup.−7/° C., the laminate coefficient of thermal expansion (CTE.sub.L) defined by: CTE.sub.L=((CTE.sub.core×T.sub.core)+(CTE.sub.clad1×T.sub.clad1)+(CTE.sub.clad2× T.sub.clad2))/(T.sub.core+T.sub.clad1+T.sub.clad2).

Apparatuses and methods for glass laminates having a controlled coefficient of thermal expansion are disclosed. In C one embodiment, a glass laminate includes a glass core having a core thickness (T.sub.core) and a core coefficient of thermal expansion (CTE.sub.core), a first glass cladding layer and a second glass cladding layer. The first glass cladding layer and the second glass cladding layer are arranged such that the glass core is disposed between the first glass cladding layer and the second glass cladding layer. The first glass cladding layer has a first cladding thickness (T.sub.clad1) and a first clad coefficient of thermal expansion (CTE.sub.clad1), and the second glass cladding layer has a second cladding thickness (T.sub.clad2) and a second clad coefficient of thermal expansion (CTE.sub.clad2). The glass laminate has a laminate coefficient of thermal expansion (CTE.sub.L) within a range of about 35×10.sup.−7/° C. to about 90×10.sup.−7/° C., the laminate coefficient of thermal expansion (CTE.sub.L) defined by: CTE.sub.L=((CTE.sub.core×T.sub.core)+(CTE.sub.clad1×T.sub.clad1)+(CTE.sub.clad2× T.sub.clad2))/(T.sub.core+T.sub.clad1+T.sub.clad2).

According to various embodiments, a back surface plate configured to form a back surface of an electronic device may include: a first glass part including a first pattern area including a pattern having a predetermined shape on a first surface; and a second glass part, at least a portion of which is disposed on the first surface of the first glass part, the second glass part including a first shape complimentary to the first pattern area, wherein the second glass part may have a color different from the color of the first glass part.

A process for room temperature substrate bonding employs a first substrate substantially transparent to a laser wavelength is selected. A second substrate for mating at an interface with the first substrate is then selected. A transmissivity change at the interface is created and the first and second substrates are mated at the interface. The first substrate is then irradiated with a laser of the transparency wavelength substantially focused at the interface and a localized high temperature at the interface from energy supplied by the laser is created. The first and second substrates immediately adjacent the interface are softened with diffusion across the interface to fuse the substrates.

A process for room temperature substrate bonding employs a first substrate substantially transparent to a laser wavelength is selected. A second substrate for mating at an interface with the first substrate is then selected. A transmissivity change at the interface is created and the first and second substrates are mated at the interface. The first substrate is then irradiated with a laser of the transparency wavelength substantially focused at the interface and a localized high temperature at the interface from energy supplied by the laser is created. The first and second substrates immediately adjacent the interface are softened with diffusion across the interface to fuse the substrates.

A process for room temperature substrate bonding employs a first substrate substantially transparent to a laser wavelength is selected. A second substrate for mating at an interface with the first substrate is then selected. A transmissivity change at the interface is created and the first and second substrates are mated at the interface. The first substrate is then irradiated with a laser of the transparency wavelength substantially focused at the interface and a localized high temperature at the interface from energy supplied by the laser is created. The first and second substrates immediately adjacent the interface are softened with diffusion across the interface to fuse the substrates.

A process for room temperature substrate bonding employs a first substrate substantially transparent to a laser wavelength is selected. A second substrate for mating at an interface with the first substrate is then selected. A transmissivity change at the interface is created and the first and second substrates are mated at the interface. The first substrate is then irradiated with a laser of the transparency wavelength substantially focused at the interface and a localized high temperature at the interface from energy supplied by the laser is created. The first and second substrates immediately adjacent the interface are softened with diffusion across the interface to fuse the substrates.

One aspect is a reflective member, which has a laminated structure in which transparent quartz glass members are formed on an upper surface and a lower surface of an opaque siliceous sintered powder layer. The opaque siliceous sintered powder layer has a thickness of 0.1 mm or more and a thickness distribution of ±0.05 mm or less. When a load is applied to each of the transparent quartz glass members on an upper surface and a lower surface of the laminated structure in a direction parallel to the laminated structure, the reflective member is fractured at a load of 5 N or more per square centimeter. The laminated structure includes a semi-transparent portion having a width of 0.01 mm or less, which has an intermediate opacity between an opacity of the opaque siliceous sintered powder layer and an opacity of each of the transparent quartz glass members.

One aspect is a reflective member, which has a laminated structure in which transparent quartz glass members are formed on an upper surface and a lower surface of an opaque siliceous sintered powder layer. The opaque siliceous sintered powder layer has a thickness of 0.1 mm or more and a thickness distribution of ±0.05 mm or less. When a load is applied to each of the transparent quartz glass members on an upper surface and a lower surface of the laminated structure in a direction parallel to the laminated structure, the reflective member is fractured at a load of 5 N or more per square centimeter. The laminated structure includes a semi-transparent portion having a width of 0.01 mm or less, which has an intermediate opacity between an opacity of the opaque siliceous sintered powder layer and an opacity of each of the transparent quartz glass members.

A method including emitting a laser beam toward a transparent workpiece such that portions of the laser beam pass through openings of a beam shaping structure and form corresponding laser beam focal lines across the transparent workpiece. The laser beam focal lines forming a plurality of defects in the transparent workpiece disposed along a contour line. The method further including separating the transparent workpiece along the contour line to provide a first workpiece section and a second workpiece section and a cut edge surface on each of the first and second workpiece sections, each cut edge including a defect region and an unaffected region. The defect region having a higher surface roughness than the unaffected region and a minimum distance of the unaffected region to the first major surface being about 20% or less of a thickness between the first major surface and the second major surface.