Showing papers by "Samsung published in 1983"

Semiconductor die-attach technique and composition therefor

Abstract: A method of attaching semiconductor die to a package substrate and a composition for such die attach is disclosed, which method and composition comprise the combination of a low and a high-melting powder with a vehicle consisting of a solvent and a binder so as to form a thick-film ink. The ink is deposited onto the package substrate and the semiconductor die with a metallized back surface is located in contact with the deposited ink. The package containing the ink and the die is heated to a temperature of approximately 160° C. so as to remove the solvent from the powders and the residual binder. Next, the package is fired at a temperature within the range of approximately 200° C. to 430° C. so as to melt the low-melting powder which bonds the chip to the package substrate. Then, a lid is sealed over the die-receiving cavity of the package by heating the package and the bonded die to a temperature within a range of approximately 400° C. to 450° C. wherein the low-melting powder remelts and the high-melting powder partially dissolves into the liquid of the remelted low-melting powder.

Linear integrated circuit for driving a d.c. motor with radio control

Abstract: The present invention relates to a linear integrated circuit for driving a d.c. motor with remote radio control comprising an amplifier B1 to amplify the signal transmitted by the transmitter, a peak detector B2 detecting the said signal, a comparator B3 triggered by the d.c. output voltage of the said detector, transistors Q1 ', Q2 ' of the driving stage circuit B4, which can invert the driving direction of the d.c. motor by on or off operation of the said transistors in accordance with the output voltage of the said comparators, a voltage regulator circuit B5 and a thermal protection circuit B6 stabilizing the said transistors thermally.

Nematic liquid crystals and method for production thereof

Abstract: The invention relates to nematic liquid crystals, especially for electro-optical components for the modulation of transmitted or reflected light, as well as for the display of numbers, symbols and images, exhibiting favorable physical characteristics, as well as to a method for the production of the new substances. It has been found that new liquid crystal 2-substituted-1,3-dioxane-5-carboxylic acid esters of the general formula ##STR1## are suited for use in electro-optical components for the modulation of the light, as well as for the display of numbers, symbols and images, and can be used alone, in mixtures with each other and/or in mixtures with additional liquid crystal or non-liquid crystal substances. In the method for the production of the new liquid crystal trans-2-substituted-1,3-dioxane-5-carboxylic acid esters, 2-substituted-1,3-dioxane carboxylic acids, with halogen donors such as thionyl chloride, sulfuryl chloride or phosphoric halides, preferably in the absence of organic bases, are converted into the corresponding acid chlorides, which are subsequently esterified in well-known fashion with alcohols or substituted phenols.

Method of manufacturing a semiconductor device

Abstract: This invention discloses EEPROM which increases an erasing voltage Vpp to be applied in a data write cycle by increasing an avalanche breakdown voltage between a source region and a semiconductor substrate in order to improve erasing efficiency, and employs a structure which strengthens the electric field at the edge of a drain region in order to let hot carrier be easily generated and to improve writing efficiency.