Matiar Howlader

McMaster University | McMaster · Department of Electrical and Computer Engineering

Wearable real-time, non-invasive personalized health monitoring sensors and low-power electronics critically necessitate alternative power supplies because batteries have proven insufficient due to their demerits of charging cycles and periodic degradation and replacement. Thermoelectric energy harnessing from human body heat via the Seebeck effect...

A plasmonic switchable polarization-insensitive metasurface absorber is proposed. The design provides two modes of operation by employing phase-change material in semiconductor and metallic phases. In this paper, we study the switchable absorption behavior of the metasurface operating in a dual-band and single-band modes targeting the mid-infrared...

The superwettability patterned aluminum surface has been shown considerable attention for emerging applications. However, the available techniques are time-consuming and require hazardous chemicals, especially toxic fluoride. In this work, the superhydrophilic-superhydrophobic patterned surface of aluminum was successfully fabricated by using nanos...

The COVID-19 pandemic has devastated the world, despite all efforts in infection control and treatment/vaccine development. Hospitals are currently overcrowded, with health statuses of patients often being hard to gauge. Therefore, methods for determining infection severity need to be developed so that high-risk patients can be prioritized, resourc...

Correction for ‘Glutamate sensing in biofluids: recent advances and research challenges of electrochemical sensors’ by Jessica Schultz et al. , Analyst , 2020, 145 , 321–347. DOI: 10.10.1039/C9AN01609K

Bisphenol A (BPA), one of the most extensively used plasticizers, is an endocrine disrupting chemical (EDC). Leaching of BPA in food, and water sources causes adverse health effects, therefore, it requires monitoring. In this work, we developed a simple, low-cost electrochemical sensor for detecting very low level of BPA in water using chemically m...

Cannabinoid sensing in biofluids provides great insight into the effects of medicinal cannabis on the body. The prevalence of cannabis for pain management and illicit drug use necessitates knowledge translation in cannabinoids. In this review, we provide an overview of the current detection methods of cannabinoids in bodily fluids emphasizing elect...

Glutamate is a nonessential amino acid and a putative neurotransmitter. When its consumption exceeds its synthesis, it becomes necessary to monitor its levels. Hence, a low-cost, sensitive and real-time monitoring of glutamate to quantify pain and detect neurodegenerative diseases is imperative to improve pharmacotherapy and early diagnosis for hea...

A simple, facile and low-cost modification of multiwalled carbon nanotubes (MWCNT) with β-cyclodextrin (βCD) through a physical (Phys) and a covalent approach via Steglich esterification (SE) is demonstrated for the detection of lead (Pb). The Pb sensing performance is governed by the amount of βCD present in the MWCNT-βCD matrix and the physical/c...

A plasmonic dual-band polarization-insensitive metasurface absorber is proposed. The design provides subwavelength and confined collection of the absorbed energy in the gaps of the structure. In this paper, we study the absorption behavior of the metasurface operating in a dual-band mode targeting the mid-infrared range suitable for energy harvesti...

Heavy metal pollution is a severe environmental problem affecting many water resources. The non-biodegradable nature of the heavy metals such as lead (Pb) causes severe human health issues, so their cost-effective, sensitive and rapid detection is needed. In this work, we describe a simple, facile and low cost modifications of multiwalled carbon na...

Monitoring of trace amount of acetaminophen and estrogen in drinking water is of great importance because of their potential links to gastrointestinal diseases, and breast and prostate cancers. The sensitive and accurate detection of acetaminophen and estrogen requires the development of advanced sensing materials that possess appropriate number of...

In this review, we discuss chemical, physical and electrochemical properties of pH-sensitive polymers and organic materials and their sensing mechanisms for healthcare applications. We find that polymers and organic materials, due to their biocompatibility and customizable electrical and electrochemical properties, can be used in pH sensors as stru...

Lead (Pb) is a highly toxic and carcinogenic heavy metal causing adverse impacts on environment and human health, thus requiring its careful monitoring. In this work, we demonstrate the integration of copper (Cu) film-based electrodes toward Pb sensing. For this, we developed a direct bonding method for Cu thin film and liquid crystal polymer (LCP)...

Wearable sensors are of interest for several application areas, most importantly for their potential to allow for the design of personal continuous health monitoring systems. For wearable sensors, flexibility is required and imperceptibility is desired. Wearable sensors must be robust to strain, motion, and environmental exposure. A number of diffe...

Copper (Cu) film bonded with polymer substrates offers better dimensional stability than that of deposited Cu especially in humid environment. However, poor adhesion is an issue in both cases. In this paper, we demonstrate a two-step, low temperature direct bonding technique for liquid crystal polymer (LCP) and copper (Cu) using oxygen plasma. The...

We report a simple, low-cost fabrication of multi-walled carbon nanotubes (MWCNT) based sensing electrodes on filter paper and flexible polydimethylsiloxane (PDMS) elastomer for electrochemical sensing of both pH and pharmaceutical contaminants, such as estrogen and bisphenol A, for the first time. A low elec-trical resistance of ~500 Ω was achieve...

Accurate, efficient, inexpensive, and multi-parameter monitoring of water quality parameters is critical for continued water safety from developed urban regions to resource-limited or sparsely populated areas. This study describes an integrated sensing system with solution-processed pH, free chlorine, and temperature sensors on a common glass subst...

We report direct bonding of liquid crystal polymer and copper film for electrochemical sensing for the first time. A peel strength of 683 g/cm was observed indicating strong adhesion. X-ray photoelectron and electrochemical impedance spectroscopies were used to characterize the sensing electrodes.

Inkjet printing is used to deposit palladium films with different morphologies and electrical properties using different precursor thermolysis atmospheres. First, the precursor is reductively decomposed into amine-stabilized palladium clusters. In air, oxygen assists the decomposition of the organoamine ligands for the palladium clusters. Small nan...

In this paper, a direct bonding technology for liquid crystal polymer (LCP) and glass is developed for the first time by using sequential plasma-activated bonding which is based on physical sputtering followed by the formation of chemically reactive surfaces. The sequential-plasma-activated surfaces of glass and LCP show high hydrophilicity with mo...

The concentration of free chlorine used for disinfecting drinking water, recreational water, and food processing water is critical for environmental and human health conditions, and should be controlled within stipulated ranges. This report, for the first time, describes a paper-based electrochemical free chlorine sensor fabricated by hand-drawing....

An inkjet printing process for depositing palladium (Pd) thin films from a highly loaded ink (> 14 wt%) is reported. The viscosity and surface tension of a Pd-organic precursor solution is adjusted using toluene to form a print-able and stable ink. A two-step thermolysis process is developed to convert the printed ink to continuous and uniform Pd fil...

Silicon-based integrated systems are actively pursued for sensing and imaging applications. A major challenge to realize highly sensitive systems is the integration of electronic, optical, mechanical and fluidic, all on a common platform. Further, the interface quality between the tiny optoelectronic structures and the substrate for alignment and c...

Nanocrystalline diamond films have been deposited by pulsed electron beam ablation from a single target and on different substrates at room temperature and under argon background gas at 0.5 Pa. The films have been deposited from a highly ordered pyrolytic graphite target on four different substrate materials, which include silicon, stainless steel,...

Continuous, real-time monitoring of the level of pH and free chlorine in drinking water is of great importance to public health. However, it is challenging when conventional analytical instruments, such as bulky pH electrodes and expensive free chlorine meters, are used. These instruments have slow response, are difficult to use, prone to interfere...

Implantable electrodes with high flexibility, high mechanical fixation and low electrochemical impedance are desirable for neuromuscular activation because they provide safe, effective and stable stimulation. In this paper, we report on detailed materials and electrical analyses of three metal implantable electrodes - gold (Au), platinum (Pt) and t...

Implantable electrodes with high flexibility, high mechanical fixation and low electrochemical impedance are desirable for neuromuscular activation because they provide safe, effective and stable stimulation. In this paper, we report on detailed materials and electrical analyses of three metal implantable electrodes – gold (Au), platinum (Pt) and t...

Implantable electrodes with high flexibility, high mechanical fixation and low electrochemical impedance are desirable for neuromuscular activation because they provide safe, effective and stable stimulation. In this paper, we report on detailed materials and electrical analyses of three metal implantable electrodes – gold (Au), platinum (Pt) and t...

In this paper, surface-activation-based nanobonding technology and its applications are described. This bonding technology allows for the integration of electronic, photonic, fluidic and mechanical components into small form-factor systems for emerging sensing and imaging applications in health and environmental sciences. Here, we describe four dif...

In this paper, surface-activation-based nanobonding technology and its applications are described. This bonding technology allows for the integration of electronic, photonic, fluidic and mechanical components into small form-factor systems for emerging sensing and imaging applications in health and environmental sciences. Here, we describe four dif...

In this paper, surface-activation-based nanobonding technology and its applications are described. This bonding technology allows for the integration of electronic, photonic, fluidic and mechanical components into small form-factor systems for emerging sensing and imaging applications in health and environmental sciences. Here, we describe four dif...

Surface-activated nanobonding of electronic, photonic, optical, fluidic and mechanical materials will be introduced for real-world applications in health and environmental systems. It provides strong bonding without the need for heating, chemicals or adhesives. Some applications of nanobonding to biosensing and biophotonic imaging systems will be d...

For heterogeneous integration in many More-than-Moore applications, surface preparation is the key step to realize well-bonded multiple substrates for electronics, photonics, fluidics and/or mechanical components without degradation in performance. Therefore, it is critical to understand how various processing and environmental conditions affect th...

For heterogeneous integration in many More-than-Moore applications, surface preparation is the key step to realizing well-bonded multiple substrates for electronics, photonics, fluidics and/or mechanical components without a degradation in performance. Therefore, it is critical to understand how various processing and environmental conditions affec...

Surface and interface characteristics of substrates are critical for reliable wafer bonding. Understanding the elemental and compositional states of surfaces after various processing conditions is necessary when bonding dissimilar materials. Therefore, we investigated the elemental and compositional states of silicon (Si), silicon dioxide (SiO2) an...

In this paper, some of the recent achievements in surface-activation-based nanobonding technology are described. This bonding technology allows for the combination of electronic, photonic, fluidic and mechanical functionalities into small form-factor systems for emerging applications in health diagnostics and screening, for example. These nanobond...

In this paper, we report on a simple, low-cost process to grow GaAs nanostructures of a few nm diameter and ∼50 nm height in Pyrex glass wafers. These nanostructures were grown by sequential plasma activation of GaAs and Pyrex glass surfaces using a low-temperature hybrid plasma bonding technology in air. Raman analyses of the activated surfaces sh...

Beyond their biocompatibility, implanted electrodes for neuromuscular stimulation require careful consideration of conductivity, stability, and charge delivery capacity (CDC) to avoid irreversible faradaic reactions. To study these requirements, metal electrodes of platinum (Pt), gold (Au), and titanium (Ti) on flexible liquid crystal polymer are f...

In this paper, surface activated nanointegration of computational, electrical, optical, and mechanical structures for intelligent telemetry, communication, and sensing systems is described. The design approach and integration of top-down systems and bottom-up devices is considered with the need for biologically compatible bonding. For the simplifie...

In this paper, a review of surface-activation-based nanobonding technology for packaging and integration is presented. In this paper, the focus will be on nanobonding technology for electronic, photonic, and fluidic devices for miniaturized biomedical and environmental-sensing systems. We describe four different nanobonding techniques that have bee...

A comprehensive investigation of the surfaces of copper through silicon vias �Cu-TSVs� and gold stud bumps is presented. These vias and stud bumps were bonded at room temperature using a nanobonding and interconnection equipment. The influence of heating on the bonded interface was also studied. In order to achieve an intimate contact between the A...

Flip chip nanobonding and interconnect system (NBIS) equipment with high precision alignment has been developed based on the surface activated bonding method for high-density interconnection and MEMS packaging. The 3σ alignment accuracy in the IR transmission system was approximately ±0.2 μm. The performance of the NBIS has been preliminarily inves...

Direct nanobonding of p-Si/n-GaAs wafers based on surface activation that uses an Argon (Ar)-fast atom beam at room temperature has been investigated. The bonding strength of the interface was 14.4 MPa at room temperature, and remained nearly constant after annealing up to 600 °C. An amorphous layer with a thickness of 11.5 nm was found across the...

This paper studies the electrochemical impedance of Platinum (Pt), Gold (Au), and Titanium (Ti) deposited on liquid crystal polymer (LCP) to understand charge transfer mechanism of implantable electrodes for neuromuscular electrical stimulation. Electrodes are fabricated through e-beam evaporation and characterized using electrochemical impedance s...

In order to investigate the high temperature application of surface activated silicon/silicon wafer bonding, the wafers were bonded at room temperature and annealed up to 600 °C followed by optical, electrical, mechanical and nanostructure characterization of the interface. Void-free interface with high bonding strength was observed that was indepe...

The fundamentals of room temperature bonding methods-surface activated bonding (SAB) and sequentially plasma-activated bonding (SPAB)-are reviewed with applications for packaging of microelectromechanical systems (MEMS) and microfluidic devices. The room temperature bonding strength of the silicon/silicon interface in the SAB and SPAB is as high as...

This article reports the sequentially plasma activated bonding (SPAB) of n–Ge with p–Si and SiO2 at low temperature. Surface activation resulted in highest hydrophilicity of Ge compared with Si and SiO2 counterparts. The highest hydrophilicity of Si, Ge and SiO2 induced by O2 RIE plasma was combined with their highest reactivity induced by MW...

To investigate the sequentially plasma-activated bonding (SPAB) mechanism of silicon/silicon wafers, the surface hydrophilicity, and the interface voids, nanostructures and chemical compositions that control the bonding quality, such as bonding strength, have been observed. Although the sequentially plasma-activated surfaces are hydrophilic, the SP...

Hybrid plasma bonding (i.e., sequentially plasma activation followed by anodic bonding) has been demonstrated for germanium and glass wafers for the first time. Void-free interface with high bonding strength has been observed at 200 °C. This improved quality is attributed to reduced surface roughness and increased hydrophilicity of sequentially act...

A novel hybrid plasma bonding (HPB) that combines sequential plasma activation (reactive ion etching followed by microwave radicals) with anodic bonding has been developed to achieve void-free and strong silicon/glass bonding at low temperature. The interfacial voids were observed at the silicon/glass interface both in the anodic bonding and in the...

Hybrid plasma bonding (i.e., sequentially plasma activation followed by anodic bonding) has been demonstrated for germanium and glass wafers for the first time. Void-free interface with high bonding strength has been observed at 200°C. This improved quality is attributed to reduced surface roughness and increased hydrophilicity of sequentially acti...

Two 4 inch silicon wafers were directly bonded using a sequentially plasma-activated bonding method (i.e. O 2 reactive ion etching (RIE) plasma followed by N 2 microwave (MW) radicals) at room temperature. The bonded wafers were annealed from 200 to 900 • C in order to explore the nucleation of voids at the interface. The plasma-induced void nuclea...

a b s t r a c t This article reports the direct bonding of aluminum (Al) [99.999% (5N), 99% (2N)] and stainless steel SUS (304, 316) without heating for sealing in the ultra high vacuum (UHV) components. For bonding, the smooth surfaces of the Al and SUS specimens were activated using argon fast atom beam (Ar-FAB) for 1e60 and 60 min, respectively,...

In this paper, we report a novel LiNbO3 ridge waveguide fabrication technique based on the combination of Annealed Proton-Exchanging (APE) and precise diamond blade dicing. The process is ultra compact and compatible with periodically polled LiNbO3 (PPLN). By selecting optimized fabrication conditions, ridge waveguide with low propagation loss and...

Two 4 inch silicon wafers were directly bonded using a sequentially plasma-activated bonding method (i.e. O2 reactive ion etching (RIE) plasma followed by N2 microwave (MW) radicals) at room temperature. The bonded wafers were annealed from 200 to 900 °C in order to explore the nucleation of voids at the interface. The plasma-induced void nucleatio...

The sequentially plasma activated bonding of silicon wafers has been investigated to facilitate the development of chemical free, room temperature and spontaneous bonding required for nanostructure integration on the wafer scale. The contact angle of the surface and the electrical and nanostructural behavior of the interface have been studied. The...

The role of nitrogen microwave (MW) radicals in sequential plasma activated bonding of silicon/silicon has been investigated through contact angle and electron energy loss spectroscopy (EELS) observations. The contact angle for the sequentially activated (using oxygen RIE time for 60 s followed by variable times of nitrogen MW) silicon surfaces was...

The sequentially plasma activated bonding (SPAB) of silicon/silicon interface has been characterized after annealing up to 900°C for packaging of micro- electro mechanical systems (MEMS) and microfluidic devices at low temperature. The bonding strength of the interface in the SPAB was as high as that of the conventional hydrophilic bonding method,...