Chip packaging technique

A hermetically sealed package for at least one semiconductor chip is provided which is formed of a substrate having electrical interconnects thereon to which the semiconductor chips are selectively bonded, and a lid which preferably functions as a heat sink, with a hermetic seal being formed around the chips between the substrate and the heat sink. The substrate is either formed of or includes a layer of a thermoplastic material having low moisture permeability which material is preferably a liquid crystal polymer (LCP) and is a multiaxially oriented LCP material for preferred embodiments. Where the lid is a heat sink, the heat sink is formed of a material having high thermal conductivity and preferably a coefficient of thermal expansion which substantially matches that of the chip. A hermetic bond is formed between the side of each chip opposite that connected to the substrate and the heat sink. The thermal bond between the substrate and the lid/heat sink may be a pinched seal or may be provided, for example by an LCP frame which is hermetically bonded or sealed on one side to the substrate and on the other side to the lid/heat sink. The chips may operate in the RF or microwave bands with suitable interconnects on the substrate and the chips may also include optical components with optical fibers being sealed into the substrate and aligned with corresponding optical components to transmit light in at least one direction. A plurality of packages may be physically and electrically connected together in a stack to form a 3D array

Pharmacokinetic evaluation of newly developed isradipine sustained release formulation

A specific and efficient method using High Performance Liquid Chromatography (HPLC) has been developed to validate the pharmacokinetics of sustained-release formulation containing Isradipine. The objective of the present study is to develop and validate PK of sustained release formulation containing Isradipine. The plasma samples of Isradipine were extracted using the protein precipitation technique (PPT). The detection wavelength of Isradipine, which was 325nm, was determined using UV spectrophotometer. Reversed phase Thermos c18 column was used for separation. 10mM ammonium acetate buffer (pH 4) and acetonitrile at a ratio of 20:80% v/v was used as the mobile phase with the flow rate of 1.0 ml/min. The linearity achieved in this method was in the range of 10-120 ng/ml. HPLC method provides extremely precise results and is an excellent and efficient method compared to others. The development of a sustained release formulation offers advantages such as prolonged blood levels of the drug and improved patient compliance. The formulated sustained release tablets containing Isradipine is capable of exhibiting sustained release properties, stable and feasible for industrial scale production. Thus they are capable of reducing the dose intake, minimize the blood level oscillations, dose related adverse effects, cost and ultimately improve the patient compliance in the hypertension