Abstract: A method for manufacturing a plastic encapsulated semiconductor device and a lead frame therefor. An external lead of a lead frame extends to one side of a substrate support serving as a heat sink and supporting a semiconductor substrate, and strips of the lead frame extend to the other end of the substrate support. The external lead and strips are clamped by upper and lower molds for plastic encapsulation so that a thin film of plastic is uniformly formed on a lower surface of the substrate support. A connecting portion between the external lead and a connecting band and the strips extending from a plastic encapsulating housing to the outside are cut.

Abstract: A method for manufacturing a plastic encapsulated semiconductor device is provided which comprises the steps of: clamping by upper and lower molds at least external leads and strips of a semiconductor device assembly formed using a lead frame which has a first connecting band connected to the external leads extending from one side of a substrate support further used as a heat sink, and a second connecting band connected to the strips having portions of small cross-sectional areas and of a predetermined length and extending from the other side of the substrate support, the cross sections being perpendicular to an extending direction of the strips, so that the substrate support may float in a cavity formed by the upper and lower molds and parts of the portions of small cross-sectional areas may be disposed in the cavity and the remaining parts thereof may be disposed between the upper and lower molds; injecting a plastic into the cavity; and cutting the portions of small cross-sectional areas of the strips whic

Abstract: A method for manufacturing a plastic encapsulated semiconductor device and a lead frame therefor. An external lead of a lead frame extends to one side of a substrate support serving as a heat sink and supporting a semiconductor substrate, and strips of the lead frame extend to the other end of the substrate support. The external lead and strips are clamped by upper and lower molds for plastic encapsulation, so that a thin film of plastic is uniformly formed on a lower surface of the substrate support. A connecting portion between the external lead and a connecting band and the strips extending from a plastic encapsulating housing to the outside are cut.

Abstract: The invention provides a lead frame for a plastic encapsulated semiconductor device wherein one of the external leads connected to a first connecting band extends from one edge of a substrate support which supports a semiconductor substrate and also serves as a heat sink, two strips are connected to a second connecting band from the other edge of the substrate support, a notch is formed between the two strips of the second connecting band to allow proper positioning of the lead frame and to decrease thermal deformation during plastic encapsulation. Further, another lead frame is provided wherein a through hole is formed extending within the substrate support in the direction of thickness thereof in order to allow uniform flow of the resin and to form a thin resin layer on the rear surface of the substrate support.

Abstract: A method for manufacturing a plastic encapsulated semiconductor device is provided which comprises the steps of: clamping by upper and lower molds at least external leads and strips of a semiconductor device assembly formed using a lead frame which has a first connecting band connected to the external leads extending from one side of a substrate support further used as a heat sink, and a second connecting band connected to the strips having portions of small cross-sectional areas and of a predetermined length and extending from the other side of the substrate support, the cross sections being perpendicular to an extending direction of the strips, so that the substrate support may float in a cavity formed by the upper and lower molds and parts of the portions of small cross-sectional areas may be disposed in the cavity and the remaining parts thereof may be disposed between the upper and lower molds; injecting a plastic into the cavity; and cutting the portions of small cross-sectional areas of the strips whic

Abstract: In an operation for winding a synthetic thread on a cylindrical bobbin for producing a full size yarn package at a winding speed more than 2500 m/min, the possible creation of defective yarn winding is positively prevented by increasing the tightness of the winding thread on a just previously formed thread layer of the yarn package, at least once in a predetermined period defined by a critical condition. Such predetermined period is defined by1.20.times.10.sup.-6 .ltoreq. (dw/dt)/D .ltoreq. 3.0.10.sup. -6wherein w represents the number of bobbin rotations per one reciprocal traverse motion, t represents the time in minutes and D represents the thickness of the thread in denier. The above-mentioned winding tightness is created by intentionally increasing the winding yarn tenson and/or increasing the contact pressure of the yarn package with a friction driving roller.