Applying Double Electric Fields to Avoid Deteriorating Movable Sensitive Parts in MEMS During Anodic Bonding

Anodic bonding between silicon and glass with dou bl e electric fields is presented.By this means,the damage caused by the electric f ield to the movable part during bonding can be avoided and the experiment result s show that.

Measuring In-Plane Micro-Motion of Micro-Structure Using Optical Flow

Optical flow method is one of the most important methods of analyzing motion images. Optical flow field is used to analyze characteristics of motion objects. According to motion features of micro-electronic mechani-cal system (MEMS) micro-structure, the optical algorithm based on label field and neighborhood optimization is presented to analyze the in-plane micro-motion of micro-structure. Firstly, high speed motion states for each fre-quency segment of micro-structure in cyclic motion are frozen based on stroboscopic principle. Thus a series of dynamic images of micro-structure are obtained. Secondly, the presented optical algorithm is used to analyze the image sequences, and can obtain reliable and precise optical field and reduce computing time. As micro-resonator of testing object, the phase-amplitude curve of micro-structure is derived. Experimental results indicate that the meas-urement precision of the presented algorithm is high, and measurement repeatability reaches 40 nm under the same experiment condition.

A New Edge-directed Subpixel Edge Localization Method

Localization of the inspected chip image is one of the key problems with machine vision aided surface mount devices (SMD) and other micro-electronic equipments. This paper presents a new edge-directed subpixel edge localization method. The image is divided into two regions, edge and non-edge, using edge detection to emphasize the edge feature. Since the edges of the chip image are straight, they have straight-line characteristics locally and globally. First, the line segments of the straight edge are located to subpixel precision, according to their local straight properties, in a 3×3 neighborhood of the edge region. Second, the subpixel midpoints of the line segments are computed. Finally, the straight edge is fitted using the midpoints and the least square method, according to its global straight property in the entire edge region. In this way, the edge is located to subpixel precision. While fitting the edge, the irregular points are eliminated by the angles of the line segments to improve the precision. We can also distinguish different edges and their intersections using the angles of the line segments and distances between the edge points, then give the vectorial result of the image edge with high precision.

Low-k integration: Gas screening for cryogenic etching and plasma damage mitigation

The integration of porous organo-silicate low-k materials has met a lot of technical challenges.One of the main issues is plasma-induced damage,occurring for all plasma steps involved during interconnects processing.In the present paper,we focus on porous SiOCH low-k damage mitigation using cryogenic temperature so as to enable micro-capillary condensation.The aim is to protect the porous low-k from plasma-induced damage and keep the k-value of the material unchanged,in order to limit the RC delay of interconnexion levels while shrinking the microchip dimension.The cryogenic temperature is used to condense a gas inside the porous low-k material.Then,the etching process is performed at the temperature of condensation in order to keep the condensate trapped inside the material during the etching.In the first part of this work,the condensation properties of several gases are screened,leading to a down selection of five gases.Then,their stability into the porous structure is evaluated at different temperature.Four of them are used for plasma damage mitigation comparison.Damage mitigation is effective and shows negligible damage for one of the gases at-50℃.

Microelectronic neural bridge for signal regeneration and function rebuilding over two separate nerves

According to the feature of neural signals,a micro-electronic neural bridge（MENB）has been designed. It consists of two electrode arrays for neural signal detection and functional electrical stimulation（FES）,and a microelectronic circuit for signal amplifying,processing,and FES driving.The core of the system is realized in 0.5-μm CMOS technology and used in animal experiments.A special experimental strategy has been designed to demonstrate the feasibility of the system.With the help of the MENB,the withdrawal reflex function of the left/right leg of one spinal toad has been rebuilt in the corresponding leg of another spinal toad.According to the coherence analysis between the source and regenerated neural signals,the controlled spinal toad＇s sciatic nerve signal is delayed by 0.72 ms in relation to the sciatic nerve signal of the source spinal toad and the cross-correlation function reaches a value of 0.73.This shows that the regenerated signal is correlated with the source sciatic signal significantly and the neural activities involved in reflex function have been regenerated.The experiment demonstrates that the MENB is useful in rebuilding the neural function between nerves of different bodies.

THREE-ELECTRODE HIGH-TEMPERATURE OXYGEN SENSOR

Using micro-electronic techniques, a high-temperature oxygen sensor with three electrodesis designed. Yttrium-doped stabilized zirconia is used to make the solid electrolyte and thesupporting substrate for the electrodes. A gold resistance thermometer is installed on thesensor to directly monitor the temperature of gas. The platinum film is covered with aporous alumina coating, to reduce the flow effect on the sensor output and prolong thesensor’s life. Tests, conducted at 650-900℃ in the mixture of oxygen and nitrogen withthe spanning 0-32.7% oxygen concentration, indicate that the sensor is of higher sensitivity,better reproducibility and durability, fast response, but relatively large current outputs areachieved simultaneously. The sensor fabricated using photolithographic reduction and thick-film metallization techniques is conductive to substantial miniaturization.