Light emitting diodes are disclosed which have increased external efficiency and are formed from silicon carbide substrates. Diodes are produced by a method which includes directing a beam of laser light at one surface of a portion of silicon carbide, and which the laser light is sufficient to vaporize the silicon carbide that it strikes to thereby define a cut in the silicon carbide portion; and then dry etching the silicon carbide portion to remove by-products generated when the laser light cuts the silicon carbide portion. The resulting diode structure includes reticulate patterned sidewalls that promote increased light emission efficiency.

High efficiency light emitting diodes

A method of producing light emitting diodes from silicon carbide with increased external efficiency is disclosed which includes directing a beam of laser light at one surface of a portion of silicon carbide, and in which the laser light is sufficient to vaporize the silicon carbide that it strikes to thereby define a cut in the silicon carbide portion; and then dry etching the silicon carbide portion to remove by-products generated when the laser light cuts the silicon carbide portion. The resulting wafer and diode structure are also dislcosed.

Method for producing high efficiency light-emitting diodes and resulting diode structures

This invention discloses a crystalline substrate based device including a crystalline substrate (102) having formed thereon a microstructure (100); and at least one packaging layer (106) which is sealed over the microstructure by means of an adhesive and defines therewith at least one gap between the crystalline substrate (102) and the at least one packaging layer (106). A method of producing a crystalline substrate based device is also disclosed.

Methods for producing packaged integrated circuit devices & packaged integrated circuit devices produced thereby

A method for singulating semiconductor wafers comprises the steps of aiming a first(302) and a second(332) laser beam over a top surface of the substrate(100); forming scribe lines(102) in the coating layer by scanning the first laser beam across the coating layer; and cutting through the substrate along the scribe line with the second laser beam to form a respective kerf. The apparatus includes a first laser having a first wavelength placed over the coating layer of the substrate, and a second laser(324) having a second wavelength different from that of the first laser placed over a surface of the substrate. The coating layer has a first absorption coefficient relative to a wavelength of the first laser and the semiconductor substrate has a second absorption coefficient less than the first absorption coefficient. Energy from the first laser beam is absorbed into the coating layer to form scribe lines therein, and the second laser beam cuts through the substrate along the scribe lines.

Dual laser cutting of wafers

A method for producing integrated circuit devices including the steps of producing a plurality of integrated circuits on a wafer having first and second planar surfaces, each of the integrated circuits including a multiplicity of pads, waferwise attaching to both said surfaces of the wafer a layer of protective material, thereafter partially cutting into the wafer and the protective material attached thereto, thereby to define notches along outlines of a plurality of prepackaged integrated circuit devices, forming metal contacts onto the plurality of prepackaged integrated circuit devices while they are still joined together on the wafer, at least a portion of said metal contacts extending into the notches and thereafter separating the plurality of prepackaged integrated circuit devices into individual devices. Integrated circuits produced according to the method are also disclosed and claimed.

Methods and apparatus for producing integrated circuit devices

The silicon substrate in which mesa semiconductor elements are formed is scribed along dicing lines by a laser. The resolidified silicon, which failed to vaporize during scribing, is etched away by sodium hydroxide solution. As a result, the silicon substrate is separated into a plurality of mesa semiconductor pellets. These pellets undergo chemical etching with a fluoric and nitric acid mixture to smooth the cut surfaces.

Method for dicing semiconductor substrates using a laser scribing and dual etch process

PURPOSE: To reduce a loss due to etching, to suppress a decrease in a yield and to improve productivity by scribing a silicon substrate by a laser, etching it with alkaline solution, separating it into a plurality of pellets, and then treating with mixed acid of hydrofluoric acid and nitric acid. CONSTITUTION: A silicon substrate 11 is scribed by a laser. Then, silicon 22 melted without vaporizing in this step, cooled and resolidified is removed by etching with alkaline hydroxide solution. Thus, the substrate 11 is separated into a plurality of pellets. The pellets are chemically etched with mixed acid of hydrofluoric acid and nitric acid. A PN junction is formed at the substrate, and the junction is cut. Further, as the solution, sodium or potassium hydroxide is used. COPYRIGHT: (C)1992,JPO&Japio

Haruyuki Goto

Papers

Method for dicing semiconductor substrates using a laser scribing and dual etch process

Manufacture of mesa type semiconductor pellet