When the size of display panel increased, the RC delay of TFTs became serious.In order to solve this problem, it is necessary to incorporate a high dielectric (high-k) material used as the gate oxide can increase the gate oxide capacitance Co, which can induce a higher drain current and higher aperture ratio. In this study, titanium silicon oxide films were grown on amorphous silicon and poly-crystal silicon by liquid phase deposition, the addition of NH4OH in the growth solution can control the PH value and prevent the amorphous and poly-crystalline silicon over etching by HF. The physical and chemical properties of titanium silicon oxide film by means of several measuring instruments, including Fourier transform infrared spectrometer (FTIR), and X-Ray diffractometer (XRD). An Al/titanium silicon oxide/a-Si or poly-Si/Si metal-oxide-semiconductor (MOS) capacitor structure was used for the electrical measurements. After oxygen and nitrogen annealing, the leakage current is improved due to the reduction of the oxygen vacancy of titanium silicon oxide film. However, the electrical characteristics can be further improved by the postmetallization annealing treatment especially under the negative electric field. Post-metallization annealing (PMA) is to use the reaction between the aluminum contact and hydroxyl groups existed on oxide surface to form active hydrogen and diffuse through the oxide to passivate the oxide traps. Therefore, titanium silicon oxide film which treated by PMA with higher dielectric constant and lower leakage current can be obtained.

The area of advanced gate dielectrics has gained considerable attention recently because semiconductor technology roadmaps predict for less than 2 nm equivalent oxide thickness (EOT) for next 10 years, and there are significant leakage current and reliability concerns for oxy-nitride in this regime. So it¡¦s an important business to use alternate high-k dielectrics instead of oxy-nitride. Titanium silicon oxide shows a low leakage current with a high dielectric constant for dielectric applications. Besides, barium doping can create additional oxygen vacancies that can enhance dielectric constant. In this study, we prepared barium doped titanium silicon by liquid phase deposition which is a novel material considered to have intermediate properties of silicon dioxide and titanium dioxide. From several characteristic measurements, we found that barium doped titanium silicon oxide with exhibiting higher dielectric constant, low leakage current and well interface state which is very promising candidates to instead of titanium silicon oxide. The physical and chemical properties of barium doped titanium silicon oxide films by means of several measuring instruments, including Fourier transform infrared spectrometer (FTIR), secondary ion spectrometer (SIMS), and X-Ray diffractometer (XRD). An Al / Ba doped titanium silicon oxide / Si metal-oxide-semiconductor (MOS) capacitor structure was used for the electrical measurements. The static dielectric constant of the O2-annealed barium doped titanium silicon oxide film can reach about 22.3. In addition, it has well leakage current density of 2.6 ¡Ñ 10-6 A/cm2 at 5 MV/cm with the equivalent oxide thickness 1.27 nm (optical thickness of 7.3 nm). It has high potential for dielectric applications.

ABSTRACT In recent years, there has been increasing demands for high dielectric materials to replace SiO2 for high-density dynamic random access memories with ultra large scale integration (ULSI). As the dimensions of the charge storage node decrease in high-density dynamic random access memories (DRAMs), TiO2 and BaTiO3 are very promising candidates for applications with exhibiting higher dielectric constant, high refractive index and high chemical stability. The physical and chemical properties of LPD thin film by means of several measuring instruments, including Fourier Transform Infrared Spectrometer (FTIR), Auger Electron Spectroscopy (AES), Secondary Ion Spectrometer (SIMS), and X-Ray Diffractometer (XRD). As for the category in the electrical properties, such as C-V curve and I-V curve, of LPD-BTO thin film is comprehended in the most important part of this chapter. Further, we try to improve these electrical properties of LPD-TiO2 and LPD-BTO thin film by post-annealing in oxygen atmosphere at several high temperatures. From leakage current density-electric field intensity voltage (J-E) and capacitance-voltage (C-V) measurements, the leakage current densities are about (LPD-TiO2: 1 ¡Ñ 10-5 A/cm2 and LPD-BTO: 5 ¡Ñ 10-9 A/cm2). And the individual dielectric constants of both films (TiO2 and BTO) are calculated about 40 and 60. This value is larger than thermal oxide, PECVD oxide, and LPD-SiO2. We also can obtain the flat band voltage shifts of LPD-TiO2 and LPD-BTO films which are about ¡V0.5V and 0V; the effective oxide charges which are calculated about ¡V4.52¡Ñ1011 cm-2 and ¡V2.27¡Ñ1012 cm-2 The future goals: (1) Raising the atomic concentration of oxygen within both films and of barium within LPD-BTO film. (2) Shortening the process in preparation of both deposition solutions. (3) Re-checking both models.

The advantages of LPD method, low temperature process, low cost, conformal growth (good step coverage), selective growth and inexpensive deposition system make the method of LPD versatile in IC fabrication. LPD-SiOF is a potential method to replace traditional method of SiOF deposition. But, some drawbacks, including slightly low dielectric constant and poor performance of J-E relationship, still exist in LPD-SiOF process. In order to improve these shortcomings, with incorporating NH4OH into the LPD solution in this experiment, the SiOF:N film with high quality and low dielectric constant can be grown on Si by the TD-LPD method. In this study, the growth rate can be controlled well within 90~550 Å/h corresponding to the NH4OH concentration range of 0.1~0.8 M at the temperature range of 23~40 ¢XC. As TD-LPD-SiOF:N film deposited with 0.8 M NH4OH incorporation, the refractive index for can be kept at a constant 1.431 and the P-etch rate can be kept between 18.3 and 19.2 Å/s during the deposition temperature changes. The best experimental condition is found that incorporating 0.8 M NH4OH will get good results. If the concentration of 0.8 M is higher or lower than 0.8 M, the electrical characteristic will become poor. A model for TD-LPD-SiOF:N deposition mechanism is proposed. From the analysis of SIMS depth profile, the deposited film can be suggested that it is a combination of N-less LPD-SiOF film and N-rich accumulated interfacial layer. The properties of N-rich accumulated layer at the interface show the least effective oxide charges and lowest leakage current density. As the thickness of TD-LPD-SiOF:N film is 800 Å, the film has the best electrical characteristic. When the thickness is below or above 800 Å, all the properties become poor. TD-LPD-SiOF:N film deposited at 40 ¢XC with 0.8 M NH4OH incorporation with a thickness of 800 Å has the best physical, chemical, electrical properties. The F content for deposited film can reach 9.8 atom %. The dielectric constant can drop to about 3.07.

In recent years, titanium oxide thin film has been studied extensively for using in optical devices and electronic devices such as waveguide and future ultra-large scale dynamic random access memory (DRAM). Titanium oxide film is very promising candidates for applications with exhibiting higher dielectric constant, high refractive index and high chemical stability. Liquid phase deposition is a novel method to grow oxide layer. It has the advantage of low-temperature deposition, good step coverage, and selective growth. We use this technology to deposition titanium oxide film instead of the conventional methods of growth titanium oxide film, such as sol-gel, sputtering, LPCVD, APCVD, and PECVD. But low deposition rate is one of the drawbacks drawbacks of LPD process. In previous study, deposition rate of titanium oxide films was very slow (6Å/min). The mixture of H2TiF6(aq) and H3BO3(aq) was used as the principal solution. In this study, we incorporated HNO3(aq) into the principal solution for enhance the deposition rate. In addition, we study the deposition rate and dielectric constant of titanium oxide films as functions of H2O addition, NH4OH(aq), and Ba(OH)2(aq) concentrations in our principal solution. We examine electrical characteristics and thickness of the titanium films by capacitance-voltage measurement and Spectroscopic Reflectance. The deposition rate of titanium oxide film increases from 6 Å/min to 475Å/min and the dielectric constant is about 36.1 with adding HNO3 and opportune NH4OH into the principal solution.

With increasing integration density of very large scale integrated (VLSI) devices, multilevel metallization technology is becoming more important than it used to be. In advanced logic devices, the interlayer dielectrics have increased to four or five layers. Silicon oxide films are used as interlayer film. One candidate for making interlayer film with a low dielectric constant is F-doped Silicon oxide (SiOF). Such films have a low dielectric constant and that moisture absorption is the main drawback in using this material. For this reason, we intend to dehydrate the SiOF films by thermal annealing treatment. It could improve the electrical properties of oxide films and obtain a reliable film with lower dielectric constant. This is our purpose in this paper to explore the electrical and chemical properties of LPD-SiOF films with annealing treatment. The chemical and electrical properties can be controlled well within 250 ~ 450 ¢J annealing treatment. The LPD-SiOF film deposited at 40 ¢J with 0.8 M NH4OH incorporation and 350 ¢J annealing treatment obtain the best electrical results. The dielectric constant can drop to about 3.2, and the leakage current density can be improved to about 1¡Ñ10-7 A/cm2 under 1.5 MV/cm. Results of this study demonstrate that the SiOF films prepared by LPD with NH4OH incorporation followed by annealing treatment is suitable for IMD application.

The purpose of this study is using titanium dioxide (TiO2) as gate oxide on thin film transistor (TFT) and discussed with their physical, chemical and electrical properties. Amorphous silicon (a-Si) and polycrystalline silicon (poly-Si) are used as substrates. The metal-organic chemical vapor deposition (MOCVD) and the liquid phase deposition (LPD) are used as the TiO2 growth methods. About the LPD growth method, ammonium hexafluoro-titanate ((NH4)2TiF6) and hexafluorotitanic acid (H2TiF6) are used as Ti sources. We are interested in two parts: (1) the growth mechanisms, physics properties, chemical properties and electrical properties of MOS structure; (2) the fabrication processes and electrical properties of devices. In the first part, we discuss the thin films characteristics on a-Si and poly-Si substrates. For the MOCVD growth method, the MOCVD-TiO2 film tends to form the poly structure. Poly structure has a higher dielectric constant, however, higher traps and dangling bonds also exist at the grain boundaries. Thus, poly structure of TiO2 film has a higher leakage current. For the LPD growth method, the film tends to form the amorphous structure. Amorphous structure has lower leakage current but also has lower dielectric constant. The film that grown from the (NH)2TiF6 source is called LPD-TiO2 film. The film that grown from the (NH)2TiF6 source is called LPD-TixSi(1-x)Oy film. Both films are incorporated with OH and F ions during the growth, the OH and F ions can be outgassed during the low temperature annealing process. In addition, appropriate F ions in the film can passivate the traps and dangling bonds. The low temperature treatments in N2 or O2 ambient and post-metallization annealing (PMA) are adopted to improve the film characteristics. On the other hand, the substrate is not a prefect structure (not a single structure). Thus the film may be influenced by substrate during the annealing treatment. In the second part, the electrical properties of TFT devices were discussed under the coplanar structure. There are several differences of the operation principle in TFT and MOSFET. A-Si and poly-Si are the un-doped substrates with many traps in the bulk. The channel should be occurred through the full depletion mode. The full depletion region is the substrate that under the gate electrode. Thus, the key point is kept the suitable thickness. Too thick, the channel can not appear. Too thin, the substrate may be over-etched. For ion implantation, due to the thinner active layer, the ion implantation energy should be lowed. In addition, the activation temperature and activation time should be adjusted suitable. We have fabricated the TFT devices with the MOCVD-TiO2 as gate oxide on poly-Si substrate. From the I-V characteristics, the Kink effect can be observed. However, the Ion/Ioff ratio is still low. We must further study how to increase the Ion/Ioff ratio.

Oftast har produktutveckling samma generella tillvägagångssätt: En specifikation för en ny produkt lämnas från en marknadsföringsavdelning till en produktutvecklingsavdelning. Produktutvecklare tar sedan fram koncept som utvecklas till prototyper för att sedan tillverkas och säljas. Tillvägagångssättet skiljer sig vanligtvis genom att olika modeller som exempelvis Lean product development eller integrerad produktutveckling används i processen. Delen av Lean product development (LPD) som används vid konceptutveckling kallas set based concurrent engineering (SBCE) och dessa begrepp är relativt nya i Sverige. Vad krävs för att arbeta med set based concurrent engineering på ett framgångsrikt sätt? Går det att identifiera viktiga faktorer vid produktutveckling med SBCE hos företag? En litteraturstudie som resulterade i en lista med fem potentiellt viktiga faktorer vid produktutveckling med SBCE gjordes inför en kvalitativ studie av fem företag. Semistrukturerade intervjuer utfördes på Husqvarna, Saab, Furhoffs, Ericsson Radio och GKN Aerospace för att samla in empiri inför analys. I analysen jämfördes företagens sätt att produktutveckla med listan som togs fram i litteraturstudien. Slutsats av studien var att några viktiga faktorer för att lyckas med produktutveckling enligt SBCE är: Bred lösningsrymd, Kunskapsbaserat bortval av koncept, Återvinning av kunskap, Tekniskt kunnig projektledning, Tvärfunktionella arbetsgrupper. Dessutom framkom att en investering i rätt ledarskap kan vara en viktig faktor vid implementering av SBCE då företagets ledning måste ha förståelse för arbetsmodellen om SBCE ska kunna resultera i en positiv effekt. / Product development usually has the same general approach: A specification for a new product is provided to the product development department from the marketing department. Product developers then generate concepts which are developed into prototypes before the products are manufactured and sold. The procedure usually differs by the use of different models such as Lean product development or integrated product development in the process. The part of Lean product development (LPD) that is used when developing concepts is called set based concurrent engineering (SBCE) and these are new concepts in Sweden. What is required to work with set based concurrent engineering in a successful manner? Is it possible to identify important factors when developing products using SBCE in companies? A literature study which resulted in a list with five potentially important factors when developing products using SBCE was created before a qualitative study was conducted at five companies. Semi structured interviews were conducted at Husqvarna, Saab, Furhoffs, Ericsson Radio and GKN Aerospace to gather data for an analysis. In the analysis, comparisons were made between the companies’ way of developing products with the list that was created in the end of the literature study. A conclusion of the study was a number of important factors when developing products using SBCE could be: Wide solution space, Knowledge based screening of concepts, Recycling of knowledge, Technically competent project management, Cross functional teams. The study also showed that an investment in the right type of leadership could potentially be an important factor when implementing SBCE since the company management need to understand the working model if SBCE is going to have a positive effect.

When the size of display panel increased, the RC delay of TFTs became serious. High dielectric (high-k) materials used as the gate oxide can increase the gate oxide capacitance Co, which can induce a higher drain current, and higher aperture ratio. Therefore, low-k materials are used for inter-metal dielectrics. Thus, it can improve the RC delay. LPD-TiO2 film on a-Si and poly-Si technology and characterization of films were described in detail in this thesis. The highest dielectric constant of 11.76 and 29.54, and lowest leakage current density of 5.45¡Ñ10-7A/cm2 at -0.45 MV/cm and 3.11¡Ñ10-1 A/cm2 at 0.45 MV/cm for the O2-annealed of LPD-TiO2film on a-Si and poly-Si can be obtained.

In this paper, we use a room temperature processing system, Liquid Phase Deposition(LPD) method, to grow silicon dioxide. The advantages are cheap equipment, low temperature growth, and no thermal stress. The quality is good enough to be used in IC devices. To inverstigate the properties of silicon Dioxide, we have done different physical and chemical test, including AES,TEM,FTIR,P-etch rate. We used the high frequency C-V curve to study the interface properties. The leakage current help to clarify the film quality. Moreover, we also discuss the growth mechanism in order to more understanding of LPD method.