P. Grabiec

Silicon ultra fast cameras for electron and γ sources in medical applications

Abstract SUCIMA (Silicon Ultra fast Cameras for electron and γ sources In Medical Applications) is a project approved by the European Commission with the primary goal of developing a real time dosimeter based on direct detection in a Silicon substrate. The main applications, the detector characteristics and technologies and the data acquisition system are described.

SOI active pixel detectors of ionizing radiation-technology and design development

This paper concerns the development of a novel monolithic active pixel radiation sensor based on SOI technology. In this device, the sensitive volume corresponds to a high resistivity SOI handle wafer and the front-end CMOS electronics is integrated in the SOI device layer. Pixel test matrices have been manufactured and are under extensive characterization. The conceptual design, together with architecture and technology issues is addressed; the latest experimental results are reported.

Monolithic active pixel sensor realized in SOI technology—concept and verification

The paper presents the concept and the verification of a novel silicon monolithic active pixel detector realized in the SOI technology. The reliability and the basic electrical characteristics of the sensor are studied and the sensor sensitivity to the ionising radiation is investigated in details.

SUCIMA - Silicon Ultra fast Cameras for electron and gamma sources in Medical Applications

Real time dosimetry is a critical issue in most radiotherapy applications. SUCIMA (Silicon Ultra fast Cameras for electron and gamma sources In Medical Applications) is a project addressing the development of an imaging technique of extended radioactive sources based on monolithic and hybrid position sensitive silicon sensors, where imaging has to be understood as the record of a dose map. The requirements for the detectors are given by the main applications, namely brachytherapy and real time monitoring of a proton beam for oncology. The key issues in the sensor and DAQ development are described together with the most relevant medical applications. SUCIMA is a project supported by the European Commission.

High-resolution hybrid pixel sensors for the e+e− TESLA linear collider vertex tracker

Abstract In order to fully exploit the physics potential of a future high-energy e+e− linear collider, a Vertex Tracker, providing high-resolution track reconstruction, is required. Hybrid silicon pixel sensors are an attractive option, for the sensor technology, due to their read-out speed and radiation hardness, favoured in the high-rate environment of the TESLA e+e− linear collider design, but have been so far limited by the achievable single point space resolution. In this paper, a conceptual design of the TESLA Vertex Tracker, based on a novel layout of hybrid pixel sensors with interleaved cells to improve their spatial resolution, is presented.

Fully depleted monolithic active pixel sensor in SOI technology

An active pixel detector, which exploits wafer-bonded silicon on insulator (SOI) substrates for integration of the readout electronics with the pixel detector, is presented. The main concepts of the proposed monolithic sensor and the preliminary tests results with ionising radiation sources are addressed. Silicon on insulator is an alternative solution for a monolithic active pixel detector, which allows integrating a fully depleted sensor and front-end electronics active layers into one silicon wafer. The main idea of the sensor relies on the use of both monolithic silicon layers (device and support layers) of the SOI substrate for fabrication of pixel detector diodes and readout electronics. Such detectors can find wide range of applications, not only in particle physics but also in medicine, space science and many other disciplines. The sensor structure and the readout configuration have been developed and the measurements of a dedicated test structure have validated the new technology of the SOI detector. Small SOI sensor matrices with 8 by 8 channels have been recently produced and tested.

Adjustment of sensivity of ISFET-type micro- and nanosensors

A study of pH sensitivity of miniature ISFET-type sensors with silicon nitride sensitive layer has been presented. 4 μm wide SOI FET microsensor process and 100 nm FinFET nanosensor process have been completed with oxygen plasma treatment. ID(VDS) and gds characteristics of the devices as well as source follower circuit output signal measurements have been reported. An influence of 1% HF etching of the gate dielectric on pH sensitivity of the sensors has been described and an explanation of phenomenon of the sensitivity adjustment has been proposed.

Design, Fabrication and Characterization of SOI Pixel Detectors of Ionizing Radiation

Development of a novel monolithic active pixel image sensor based on SOI technology is presented. Active pixel test matrices have been recently manufactured and are under extensive examination. This paper describes the concept of the device and shows the most recent results.

Polymer microfluidic bioreactor fabrication by means of gray scale lithography technique

In this paper we present a new method of polymer microfluidic bioreactor fabrication by means of a gray scale lithography technique. As a result of the gray scale lithography process the 3D model of the bioreactor is defined in photoresist. The obtained model serves as a sacrificial layer for the subsequent transfer of the 3D shape into the polymer material. The proposed method allows simultaneous definition of both the overall bioreactor geometry and the multi steps cell traps in a single photolithography step. Such microfluidic structure can be used for sorting cells based on their size. The developed solution significantly simplifies the production technology and reduces its costs in comparison to standard photolithography techniques.

Gravimetric measurements with use of a cantilever for controlling of electrochemical deposition processes

In this paper we describe the method for monitoring the progress of electrochemical deposition process. The procedure allows to control the deposition of metals as well as conductive polymers on metallic seed layer. The method is particularly useful to very thin layers (1-10 nm) of deposited medium which mechanical or optical methods are troublesome for. In this method deposit is grown on the target and on the test silicon micro-cantilever with a metal pad. Galvanic deposition on the cantilever causes the change of its mass and consequently the change of its resonance frequency. Changes of the frequency is measured with laser vibro-meter then the layer thicknesses can be estimated basing on the cantilever calibration curve. Applying this method for controlling of gold deposition on platinum seed layer, for improving the properties of the biochemical sensors, is described in this paper.