摘要:
A semiconductor accelerometer device is formed on an SOI substrate by micro-machining. A movable unit is supported at both ends, and a weight portion is movable in response to acceleration exerted in the detection direction. A movable electrode is formed in a comb shape integrally with the weight portion. A pair of fixed electrodes in a comb shape are cantilevered and interleaved with the movable electrode to face the movable electrode. A plurality of through holes is provided in the electrodes so that the electrodes have Rahmen structure which is a series of rectangular frames. This structure reduces the weight of each electrode while increasing the strength against twist force. The electrodes are less likely from breaking in response to an acceleration exerted in a direction perpendicular to the normal detection direction because of reduced weight.
摘要:
In a method for manufacturing a semiconductor acceleration sensor, a movable portion including a mass portion and movable electrodes is formed in a single crystal silicon thin film provided on a silicon wafer through an insulation film by etching both the single crystal silicon thin film and the silicon wafer. In this case, the movable portion is finally defined at a movable portion defining step that is carried out in a vapor phase atmosphere. Accordingly, the movable portion is prevented from sticking to other regions due to etchant during the manufacture thereof.
摘要:
A method of manufacturing a semiconductor device is provided. The device is manufactured with use of an SOI (Silicon On Insulator) substrate having a first silicon layer, an oxide layer, and a second silicon layer laminated in this order. After forming a trench reaching the oxide layer from the second silicon layer, dry etching is performed, thus allowing the oxide layer located at the trench bottom to be charged at first. This charging forces etching ions to impinge upon part of the second silicon layer located laterally to the trench bottom. Such part is removed, forming a movable section. For example, ions to neutralize the electric charges are administered into the trench, so that the electric charges are removed from charged movable electrodes and their charged surrounding regions. Removing the electric charges prevents the movable section to stick to its surrounding portions.
摘要:
A method of manufacturing a semiconductor device is provided. The device is manufactured with use of an SOI (Silicon On Insulator) substrate having a first silicon layer, an oxide layer, and a second silicon layer laminated in this order. After forming a trench reaching the oxide layer from the second silicon layer, dry etching is performed, thus allowing the oxide layer located at the trench bottom to be charged at first. This charging forces etching ions to impinge upon part of the second silicon layer located laterally to the trench bottom. Such part is removed, forming a movable section. For example, ions to neutralize the electric charges are administered into the trench, so that the electric charges are removed from charged movable electrodes and their charged surrounding regions. Removing the electric charges prevents the movable section to stick to its surrounding portions.
摘要:
Plural semiconductor chips such as acceleration sensor chips formed on the first surface of a substrate are separated into individual pieces by dicing the substrate from the second surface thereof. A groove surrounding each sensor chip, along which the sensor chip is diced out, is formed at the same time the sensor chip is formed on the first surface. Before dicing, a protecting sheet covering the first surface is pasted along the sidewalls and the bottom wall of the groove. The groove is made sufficiently wide to ensure that the protecting sheet is bent along the walls of the groove without leaving a space between the groove and the protecting sheet. Thus, dicing dusts generated in the dicing process are prevented from being scattered and entering the sensor chip.
摘要:
A semiconductor acceleration sensor, which prevents an adhesion of a movable portion to a fixed portion due to an electrostatic force generated during being handled. The acceleration sensor has a sensor portion and a handling portion. The sensor portion has a first semiconductor layer; a movable portion including a weight portion supported to the first semiconductor layer for moving in accordance with an acceleration externally applied thereto and movable electrodes integrally formed with the weight portion; and fixed electrodes having a detection surface confronted to a detection surface of the movable electrodes and supported to the first semiconductor layer. The handling portion is to be contacted during being handled, and is provided at surrounding portion of the sensor portion with a trench interposed therebetween. The sensor portion is electrically insulated from the handling portion by the trench.
摘要:
A protective sheet is fixed to a jig, and regions of the protective sheet corresponding to regions where dicing-cut is to be performed are removed to form grooves. Then, a semiconductor wafer is bonded to the protective sheet at an opposite side of the jig, and the jig is detached from the protective sheet and the semiconductor wafer bonded together. After that, the semiconductor wafer is cut into semiconductor chips by dicing along the grooves of the protective sheet. Because the protective sheet is not cut by dicing, no scraps of the protective sheet is produced, thereby preventing contamination to the chips.
摘要:
A method for manufacturing a semiconductor device having a movable portion includes the steps of: forming a trench on a semiconductor layer so that the trench reaches an insulation layer; and forming a movable portion by etching a sidewall of the trench so that the semiconductor layer is separated from the insulation layer. The steps of forming the trench and forming the movable portion are performed by a reactive ion etching method. The insulation layer disposed on the bottom of the trench is prevented from charging positively in the step of forming the trench. The insulation layer disposed on the bottom of the trench is charged positively in the step of forming the movable portion.
摘要:
A method for manufacturing a semiconductor device having a movable portion includes the steps of: forming a trench on a semiconductor layer so that the trench reaches an insulation layer; and forming a movable portion by etching a sidewall of the trench so that the semiconductor layer is separated from the insulation layer. The steps of forming the trench and forming the movable portion are performed by a reactive ion etching method. The insulation layer disposed on the bottom of the trench is prevented from charging positively in the step of forming the trench. The insulation layer disposed on the bottom of the trench is charged positively in the step of forming the movable portion.
摘要:
A method for manufacturing a semiconductor device having a movable unit includes a step of forming an SOI substrate that includes a semiconductor substrate, an insulating layer, and a semiconductor layer such that the insulating layer is located between the semiconductor layer and the semiconductor substrate. The method further includes a step of dry etching the semiconductor layer to form a trench with a charge prevented from building up on a surface of the insulating layer that is exposed at a bottom of the trench during the dry etching. The method further includes a step of dry etching a sidewall defining the trench at a portion adjacent to the bottom of the trench to form the movable unit. The later dry etching is performed with a charge building up on the surface of the insulating layer such that etching ions strike to etch the portion of the sidewall.