摘要:
An etching method for a silicon substrate, which can easily smooth the etching surface of the (110)-oriented silicon, is disclosed. A container is filled with KOH solution. In the KOH solution is immersed a (110)-oriented silicon wafer having a PN junction and is also disposed a platinum electrode plate to face the silicon wafer. To between a platinum electrode of the silicon wafer and the platinum electrode plate are connected a constant voltage power source, an ammeter and a contact in series. A controller starts etching from one surface on which the PN junction is formed, and terminates voltage application when the specified time lapses after the formation of an anodic oxide film is equilibrated with the etching of the anodic oxide film on the etching surface on the PN junction part. In this case, the controller detects flowing current through the ammeter, and the point of time when the equilibrium state is obtained is the point of inflection of the detected current to the constant current after the peak thereof.
摘要:
On a back face of a silicon wafer before dicing, tapered grooves having sloped side walls are formed by anisotropic etching along with thin portions. Strain gauges are formed on each thin portion, thereby forming a sensor chip on the silicon wafer. The back face of the silicon wafer is attached to a self-adhesive seat. Thereafter, the silicon wafer is cut along the grooves by a dicing blade to divide it into each sensor chip. In dicing, the side faces of the dicing blade cut the sloped side walls of the tapered grooves. As a result, the silicon wafer is diced into individual sensor chip having no cracks and chippings.
摘要:
A semiconductor pressure detection device includes a diaphragm formed at a portion of a P- conductivity type semiconductor substrate having a reduced thickness. Gauge resistors are formed on the surface of an N- conductivity type semiconductor layer formed on the substrate. An N+ conductivity type diffusion layer is formed in the N- conductivity type semiconductor layer to fix the electric potential of the N- conductivity type layer. The first conductivity type area surrounds the diaphragm. Therefore, when the N- conductivity type area is supplied with electric potential, the potential gradient in the N- conductivity type layer is small. Thus, the leakage current which flows to a pn junction between the gauge resistors and the N- conductivity type area is reduced.
摘要:
A pair of signal voltages outputted from a bridge circuit composed of plural strain gauges are linearly amplified individually by a pair of amplifiers, whereupon a difference between the pair of signal voltages is detected. The pair of amplifiers are formed respectively in regions that are symmetrical with each other on a chip. As a result, variations in the output characteristics between the amplifiers are decreased.
摘要:
A semiconductor pressure sensor includes a diaphragm of an octagonal shape formed on a (110) silicon substrate by anisotropic etching. When a distance between two sides of the diaphragm, which are defined by intersecting lines of a (110) face and a (111) face of the silicon substrate, is represented as L1 and a length of a side of the diaphragm, which is defined by an intersecting line of the (110) face and a (100) face, is represented as L2, the diaphragm is formed so as to satisfy the following relationship: 0.65
摘要:
A hybrid integrated circuit having a lead frame electrically connected to electronic components by means of a silver (Ag) paste, the hybrid integrated circuit comprising: an electroless-plated coating on the lead frame, the coating being free from an insulating surface oxide layer at least in a connection area in which the electrical connection is provided. A process of producing this hybrid integrated circuit comprises: a first step of electroless-plating a lead frame by using a phosphorus-containing reducing agent to form a coating on the lead frame; a second step of mounting electronic components on the lead frame and then electrically and mechanically connecting the former to the latter by means of an electroconductive paste; and a third step of maintaining the surface of the electroless-plated coating free from a phosphorus-containing oxide layer during the connecting operation.
摘要:
A process for epitaxially growing a compound semiconductor layer containing at least arsenic on a single crystal silicon substrate, which prevents the silicon impurity from intruding said compound semiconductor layer. The process comprises supplying one of the starting material gas, ASH.sub.3, into the reaction furnace to effect growth, but in such a manner that the AsH.sub.3 gas is pyrolyzed in advance to thereby supply arsenic alone either in an atomic or a molecular state. The GaAs layer is thus epitaxially grown on a single crystal silicon substrate in the crystal growing chamber, i.e., the reaction furnace in the apparatus, under an atmosphere comprising atomic or molecular arsenic at a temperature in the range of from 400.degree. to 650.degree. C. and at a vacuum degree of about 0.1 Pa. By thus epitaxially growing GaAs layer under an atmosphere comprising atomic or molecular arsenic, the intrusion of silicon impurity into the GaAs layer during its growth can be effectively prevented. Furthermore, an undoped GaAs layer, a p-GaAs layer, and an n-GaAs layer in this order can be deposited on the silicon substrate consecutively by using carbon (C) as a p-type dopant which can be supplied from trimethylgallium, thereby realizing a steep step-like junction at the n-GaAs/p-GaAs interface.
摘要:
A control apparatus for a dazzle-free reflection mirror of a vehicle is disclosed. The control apparatus is provided with a rear light sensor and a circuit for driving the reflection mirror into a dazzle-free operation in accordance with the intensity of the rear light detected by the rear light sensor when a light switch is turned on. The control apparatus is further provided with a mirror adjusting device for adjusting the reflection angle of the reflection mirror and a detecting circuit for detecting the adjusting operation of the mirror adjusting device. When the detecting circuit detects the adjusting operation, the dazzle-free operation of the reflection mirror is disabled even if intensive light is incident to the reflection mirror from the rear of the vehicle.
摘要:
In a vehicle having an interior room mirror and a pair of exterior right and left side mirrors, a single photo sensor is provided for detecting an intensity of light incident from the rear of the vehicle. A driving circuit drives both the room mirror and the side mirrors into a dazzle-free condition in common when the photo diode detects the intensive rear light. Alternatively two photo sensors are provided for detecting not only the intensity of the rear light but also direction of the rear light and both the room mirror and one of the right and left side mirrors are driven into the dazzle-free condition in accordance with both the intensity and direction of the rear light.
摘要:
A reflection mirror using a liquid crystal cell is disclosed. A first thin film consisting of one of magnesium difluoride, silicon dioxide, silicon monoxide or titanium dioxide is formed on a glass substrate supporting the liquid crystal cell and a thin aluminum film is formed on the first thin film as a reflection mirror layer. Adhesiveness of the thin aluminum film to the glass substrate is strengthened by the first thin film. A second thin film is formed on the thin aluminum film to protect the same from being hurt. The reflection mirror may be used as a dazzle-free reflection mirror of an automotive vehicle.