Thin glass substrate with high bending strength and method for producing same

A method for producing a structured glass disk, comprising:

• providing a glass disk having a thickness of less than 50 μm between opposite side faces;
• directing a laser beam of an ultrashort pulsed laser onto the glass disk, the laser beam having a wavelength at which glass of the glass disk is transparent so that the laser beam can penetrate into the glass disk;
• focusing the laser beam to produce an elongated focus within the glass disk, the laser beam having an intensity sufficient to produce a channel within the glass disk along the elongated focus;
• moving the laser beam and the glass disk relative to one another along a ring-shaped path so that the laser beam introduces a plurality of channels adjacent to one another to define a workpiece in the glass disk with the ring-shaped path encompassing the workpiece and with the workpiece remaining connected to surrounding sections of the glass disk;
• exposing the glass disk to an etchant so that the etchant intrudes into the plurality of channels;
• and
• chemically toughening, after exposing to the etchant, the glass disk and the at least one workpiece,
• wherein the step of chemically toughening comprises immersing the glass disk into an ion exchange bath such that alkali ions penetrate into the plurality of channels and effect an ion exchange in glass surrounding the plurality channels in inner sections of the glass disk, the inner regions being deeper within the glass disk than a depth of an ion exchange layer on the opposite side faces of the glass disk, and
• wherein the workpiece, after the step of exposing the glass disk to the etchant, remains connected to the surrounding sections of the glass disk by connecting sections, wherein the connecting sections have a width that is at most twice the depth of the ion exchanged layer.

A method for producing a structured glass disk, comprising:

• providing a glass disk having a thickness of less than 50 μm between opposite side faces;
• directing a laser beam of an ultrashort pulsed laser onto the glass disk, the laser beam having a wavelength at which glass of the glass disk is transparent so that the laser beam can penetrate into the glass disk;
• focusing the laser beam to produce an elongated focus within the glass disk, the laser beam having an intensity sufficient to produce a channel within the glass disk along the elongated focus;
• moving the laser beam and the glass disk relative to one another along a ring-shaped path so that the laser beam introduces a plurality of channels adjacent to one another to define a workpiece in the glass disk with the ring-shaped path encompassing the workpiece and with the workpiece remaining connected to surrounding sections of the glass disk by connecting sections;
• exposing the glass disk to an etchant so that the etchant intrudes into the plurality of channels and reduces the thickness of the glass disk by 0.2 μm to 10 μm the workpiece remaining connected to surrounding sections of the glass disk by connecting sections having a width;
• chemically toughening, after exposing to the etchant, the glass disk and the at least one workpiece to provide a depth of an ion exchanged layer, the width being at most twice the depth;
• and
• separating the at least one workpiece from the glass disk at the surrounding sections after the step of chemically toughening.