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The electro-optic effects in silicon include Kerr effect, plasma dispersion effect, and Franz-Keldysh effect etc.. Silicon does not have the linear electro-optic effect in the bulk because of the inversion symmetry, which restricts the development of the silicon-based optoelectronics and silicon photonics. However, the electric field can destroy the inversion symmetry of silicon, and produce so-called electric-field-induced linear electro-optic effect. In intrinsic or near-intrinsic silicon, these electro-optic effects exist simultaneously. In this paper, a transverse electro-optic modulation system was designed to detect these electro-optic effects. The electric-field-induced linear electro-optic effect was demonstrated in the space charge region of silicon sample and distinguished from Kerr effect based on the different frequency response. The relationship between the linear electro-optic signal and the azimuth angle of the analyzer was measured too, which was used for distinguishing the electric-field-induced linear electro-optic effect from the plasma dispersion effect. The results showed that the electric-field-induced linear electro-optic effect was stronger than Kerr effect and the plasma dispersion effect in the near-intrinsic silicon samples.

The MEMS silicon-micro-machining is the main MEMS technology, which includes the surface-silicon-micro-machining and the bulk-silicon-micro-machining technology; however the bulk-silicon micro-machining technology has a wide application. In this paper, the formation procession of electron multiplier on n-type Silicon substrate by bulk-silicon-micro-machining technology was investigated. A series of electrochemical etching experiments and tests were carried out in three poles electrobath system using HF electrolyte with different concentration. The rate of photoelectrochemical etching on the macropore depends on a few technological parameters, such as doping concentration, operating bias, illumination intensity of the light, HF concentration, and so on. It was found that the formation possibility of the macropore array is directly correlated with crystal orientation of n-type Silicon substrate.

Microsphere plate (MSP) is a new type of electron multiplier device. It is similar to the traditional microchannel plate (MCP) in dimensions and model of operation. Compared with the MCP electron multiplier, the MSP has some unique characteristics such as a high electron gain, without ion feedback and easy to be fabricated, thus it is widely used in the fields of imaging and detecting. However, there are some key technologies to fabricate a satisfied MSP. In this paper, the whole fabrication process of MSP was introduced and some of major processes such as the formation of glass beads, the sintering of MSP body, and the formation of dynode and electrodes were specially discussed. At the end of the paper, the optimal processed for the fabrication of MSP was given.

By observing two-photon response and anisotropy of the light-induced voltage in Si-Al Schottky barrier potential of the Si MSM (Metal-Semiconductor-Metal) planar structure two-photon response optical detector. It is certified from the experimental and theoretical analysis that the built-in electric field generated by the Schottky barrier potential will induce the phenomena of optical rectification in Si photodiode. Thus, it is deduced that there must be double-frequency absorption (DFA) caused by phase-mismatch in the mechanism of two-photon response of Si photodiode. If the intensity of the built-in electric field is strong enough, the DFA will be the main feature of the two-photon response.

The MCP ion barrier film in low-light-level imaging tube and its process techniques were introduced in this paper. The electron transmittance of this film was studied. The results of half field-of-view testing comparisons and the concept of dead voltage were presented. The dead voltage curve and the relation between dead voltage and thickness of film were tested. The composition of film was analyzed by XPS.

The formation of deep macropore array of p-type Silicon in HF electrolyte has been investigated. Then a series of electrochemical etching experiments and tests were carried out in three poles electrobath using different concentration HF electrolyte. HF concentration is a very important factor that determined whether electrochemical reaction was accomplished or not. By means of theoretical analysis and investigation, it is generally assumed that etching proceeds through sequential reaction of Si-H groups with F- to form Si-X, which determined whether electrochemical etching reaction was carried out or not. The electrochemical etching of p-type Silicon macropore array in aqueous fluoride solutions is satisfied with economic requirements for costs of fabricating deep macropores. The consequences are benefit to Silicon electrochemical deep macropore array etching technology.

This paper reports on a silicon micro-hole arrays (Si-MHA) prepared by Inductively Coupled Plasma (ICP) etching, a dry etching method. By ICP etcher, we carried out several experimental researches and process exploration for micromachining Si-MHA. The mechanism of lateral etching, sidewall passivation, gas micro-transport and some process parameters in Si-MHA micromachining, such as gas switching time, flow rate, etching rate, were analyzed. The footing effect, lag effect, longitudinal strips and RIE grass effect occurred in the ICP etching process were also studied. These process problems had reappeared in the micro-hole arrays process though these problems had be solved in the field of integrated circuits process and microelectromechanical system (MEMS). The study results reported here had demonstrated a Si-MHA that the diameter was 15 μm, the center distance 30 μm, and the depth 240 μm prepared by ICP, and had led the author to believe that the deep pore structure and the deep trench with high aspect ratio were very different in etching process. The former is a closed structure for the gas transport, and the latter is an open structure, so the process of deep hole structure is a puzzle in micromachining and MEMS technology.

This paper reports on a silicon mcrochannel arrays prepared based on bulk-micromachining technology, dry etching technology and electrochemical process respectively. In dry etching, a silicon microchannel plate (Si-MCP), with 15-30 aspect ratio of the microchannel, 6-20 µm, 6-8 µm space and 150-300µm depth, were prepared by Inductively Coupled Plasma (ICP). The phenomenon ofplasma etching lag and the morphology ofthe microchannel array in dry processing were analyzed and discussed.In wet process, both p-type and n-type silicon was selected as the substrate for microchannel arrays. A inducing pit arrays was first prepared by oxidation, lithography, KOH etching, and then a square channel arrays that has 4 µm length of side and 2 µm space were formed by electrochemical etching in hydrofluoric acid in three poles electrolyzing cell, which can yield straight holes with high aspect ratio. The electrochemical mechanism of silicon anisotropy etching, the parameters of three pole electrolyzing cell, and the inducing pit and channel morphology were investigated and discussed. The results shows that the high aspect ratio of silicon microchannel arrays can be made by both dry and wet etching processes. The ICP process yield a microchannel arrays with uneven, re-entrant, notched and ripples surface within the channel. The electrochemical process for silicon microchannel arrays has lower cost than ICP process.

Introduced the construction of the experiment system of the laser probe measurements based on electro-optic sampling technique. Analyzed the relationship between the width of the optical pulses and the signal noise ratio of detection. The function of different stage circuit internal to the high-speed dynamic divider circuit chip have been measured with the double-frequency phase sweeping technique. A detail analysis about the chip failure have been given.