Учитесь читать. Текст 2.10. Прочитайте текст и укажите факторы, вли­яющие на качество резиста

Текст 2.10. Прочитайте текст и укажите факторы, вли­яющие на качество резиста. Значения выделенных слов вы сможете понять из контекста.

Photoresists

Photoresists are high-sensitive materials used to generate etched patterns in substrates. The quality of the etched images de­pends upon the success of every step in the process, and the image flaws may be due to resist or nonresist imperfections, or to condi­tions which underline resist performance. Some fundamental factors influencing resist performance include adherence coating thickness, heat treatment, and resist response to various energy sources. Let us start with adherence.

A strong bond between photoresist and substrate is essential to minimize dimensional changes during development and under­cutting or loss of adherence during etching. The intimate contact between resist and substrate required for strong adhesion can be inhibited by surface impurities or resist components. Zones of weakness can be created by surface contaminants such as dust, oil, absorbed gases (particularly absorbed water), dopant ions, or monolayers of previous resist coatings. Removal of obvious visible impurities such as grease, fingerprints, or dust can give an apparently clean surface, but contamination is often insidious (опас­ный) because it is invisible. Weakly adsorbed layers of tobacco smoke, water vapor, vacuum pump vapors, or nonstripped resist components may be present, even though difficult to detect. Condensing one's breath on the surface or placing the wafers on a cold plate can sometimes reveal an adsorbed pattern on unetched wafers after resist stripping.

 

Текст 2.11. Прочитайте текст и сделайте аннотацию на английском языке. Используйте следующие клише:

1.... deals with; 2.... is largely as a result of; 3.... is discussed; 4.... offers properties; 5. to sum up...

Ceramic-to-Metal Seals

Ceramic-to-metal seals are a natural extension of the state-of-the-art where adverse temperature, shock and vibration condi­tions prevail. Alumina ceramics are widely used for high-perfor­mance electronic applications because of their excellent properties and moderate costs. Beryllia ceramic-to-metal seals are available but generally limited to where high heat transfer is needed.

The alumina ceramic family offers a combination of desirable properties for ceramic-to-metal seals:

Electrical — high resistance, low losses, and high dielectric strength.

Mechanical — high compressive, tensile, and flexible strength, high impact strength and high hardness.

Thermal — intermediate thermal expansion coefficient that enables sealing to many metals and matching components, good thermal conductivity, good thermal shock resistance, and good high temperature properties.

Chemical — extremely stable and surface capable of with­standing harsh chemicals and cleaning procedures.

 

Текст 2.12. Прочитайте текст. Изложите на англий­ском языке основные требования, предъявляемые к мате­риалам.

Materials Requirements

The following are the general requirements for a material for interconnects and contacts: high electrical conductance, low ohmic contact resistance, electromigration, stable contacts (with silicon and final metallization), corrosion and oxidation resistance, high temperature stability, strong adhesion characteristics.

One of the primary considerations is to obtain a material with high electrical conductivity and low ohmic contact resistance. It should also have good electromigration resistance and be stable when in contact with silicon and/or oxide and the final metalliza­tion.

These parameters must be maintained throughout the high temperatures encountered during processing; i.e., to maintain their metallurgical integrity. This requires that the melting point of the materials used be much higher than conventional process temperatures.

 

2.25. Дайте классификацию пленочных материалов. Используйте схему:

 

Film Materials

 

| resistive 1	1 capacitive I	| conductive |	active
Titanium	Silicon oxides	Aluminium	Silicon
Rhenium	Silicon nitrides	Gold	Cadmium sulphide
Molybdenum	Aluminium oxide	Silver	CdTe
Tantalum	Barium titanite	Tin	Organic semiconductors
		Copper

Рис.2

 

2.26. Сравните несколько материалов, используемых в микроэлектронике, по их физическим, электрическим, оп­тическим и другим свойствам.

 

2.27. Подготовьте схему (на английском языке), пока­зывающую сходство и различие материалов, используе­мых в микроэлектронике.