Effect of adding 0.3wt% Ni into the Sn-0.7wt% Cu solder - Part II: Growth of intermetallic layer with Cu during wetting and aging

The growth behavior of intermetallic layer with or without adding 0.3 wt% Ni into the Sn-0.7Cu solder was studied during the wetting reaction on Cu-substrate and thereafter in solid-state aging condition. The Cu-solder reaction couple was prepared at 255, 275 and 295 °C for 10 s. The samples reacted at 255 °C were then isothermally aged for 2-14 days at 150 °C. The reaction species formed for the Sn-0.7Cu/Cu and Sn-0.7Cu-0.3Ni/Cu soldering systems were Cu6Sn5 and (CuNi)6Sn5, respectively. The thickness of the intermetallic compounds formed at the solder/Cu interfaces and also in the bulk of both solders increased with the increase of reaction temperature. It was found that Ni-containing Sn-0.7Cu solder exhibited lower growth of intermetallic layer during wetting and in the early stage of aging and eventually exceeded the intermetallic layer thickness of Sn-0.7Cu/Cu soldering system after 6 days of aging. As the aging time proceeds, a non-uniform intermetallic layer growth tendency was observed for the case of Sn-0.7Cu-0.3Ni solder. The growth behavior of intermetallic layer during aging for both solders followed the diffusion-controlled mechanism. The intermetallic layer growth rate constants for Sn-0.7Cu and Sn-0.7Cu-0.3Ni solders were calculated as 1.41 × 10-17 and 1.89 × 10-17 m2/s, respectively which indicated that adding 0.3 wt% Ni with Sn-0.7Cu solder contributed to the higher growth of intermetallic layer during aging. © 2006 Elsevier B.V. All rights reserved.

Meeting the emotional needs of parents who have a child with complex needs

The physical and financial demands of caring for a child with complex needs are acknowledged by health professionals. However, the emotional needs of parents are not often recognized by health professionals until parents are at a heightened level of stress. This paper is based on a literature review of current articles, research papers and government documentation. The focus is on the emotional impact to parents who have a child with complex needs, particularly at the point of diagnosis. The paper explores how health professionals, and nurses in particular, should meet the emotional needs of parents in order to support them more effectively. Giving birth to a child with severe health problems impacts upon parents at an emotional time of transition, particularly if there were no concerns identified during pregnancy. For some parents a grief response or state of chronic sorrow may be triggered. The reality of caring for a baby who is critically ill or disabled can be an enormous and unexpected shock for both parents. Parents need emotional support and guidance, as they may have to change their expectations for their child’s development and even life span. It is important for nurses to realise that if parents’ emotional needs are unmet it can lead to clinical depression or mental illness. Primary support often comes from parent support groups rather than health professionals. The review highlights factors affecting parents’ emotions and discusses how early support, home visits and practical help can all help to alleviate parents’ emotional stress.

Adult personality inconsistency and problems with parents: uncovering the roots of the false self

Research has established that individuals who tend to vary their personality depending on who they are with, show a variety of signs of psychological maladjustment in comparison to those who do not; they show more negative affect (Baird, Le and Lucas, 2006), lower life satisfaction (Suh, 2002), lower self-esteem (Sheldon et al., 1997), lower role-satisfaction (Donahue et al., 1993), higher rates of depression (Lutz and Ross, 2003), more anxiety (Diehl, Hastings and Stanton, 2001) and poorer physical health (Cross, Gore and Morris, 2003). It has also been shown that personality variability is positively related to the experience of inauthenticity and falsity (Sheldon et al., 1997). Donahue, Roberts, Robins and John (1993) found that personality inconsistency of this type is related to tension within the family. Psychoanalytic theory has also linked the operation of an adult false self to experiences with parents, particularly in early life (Winnicott, 1960). It was hypothesized that personality variability and the adult experience of falsity in social situations would be related to an emotionally unstable relationship with parents. The method to test this comprised a questionnaire-based survey given to a non-clinical population. The final sample comprised 305, with 193 women and 112 men, aged from 19 to 55. The first questionnaire asked participants to rate personality traits, including emotional stability, in three social contexts - with parents, with friends and with work colleagues. The second part involved 3 questions; participants were asked to select in which of the aforementioned three social contexts they felt “most themselves”; in which they were “most authentic” and in which they “put on a front”. It was found, consistent with predictions, that an index of overall personality variability calculated from the personality questionnaire correlated strongly with emotional instability around parents (r = 0.46, p<0.001), while not correlating with emotional instability in either of the other two contexts measured. This suggests a specific link between a person’s relationship with their parents and their overall personality integration. Furthermore, it was found that participants who cited one of the three social contexts (parents, friends, work colleagues) as being one in which they were “more themselves” or “more authentic” had significantly higher ratings of emotional instability with parents than those participants who found that they were equally authentic across settings (F = 9.8, p<0.005). The results suggest a clear link between a person’s relationships with their parents and their adult personality integration. An explanation is that individuals who experience an anxious or ambiguous attachment with their parents in childhood may fear rejection or abandonment in later life, and so habitually adapt their personality to fit in to social contexts as adults, in order to be accepted by others and to minimize the possibility of social rejection. These individuals meanwhile retain an emotionally unstable relationship with their parents in adulthood. This interpretation is speculative but is open to empirical testing. Clinicians should be aware that attachment problems with parents may underlie poor personality integration in adulthood.

Meeting the emotional needs of parents who have a child with complex needs

The physical and financial demands of caring for a child with complex needs are acknowledged by health professionals. However the emotional needs of parents are not often recognised by health professionals until parents are at a heightened level of stress. This paper is based on a literature review of current articles, research papers and government documentation. The focus is on how health professionals, and nurses in particular should meet the emotional needs of parents who have child with complex needs, particularly at the point of diagnosis. Giving birth to a child with severe health problems impacts upon parents at an emotional time of transition, particularly if there were no concerns identified during pregnancy. For some parents a grief response or state of chronic sorrow may be triggered. The reality of caring for a baby who is critically ill or disabled can be an enormous and unexpected shock for both parents. Parents need emotional support and guidance, as they may have to change their expectations for their child’s development and even life span. Primary support often comes from parent support groups rather than health professionals. The review discusses how home visits, practical help and early support can all help to alleviate stress. It is important for nurses to realise that if parents’ emotional needs are unmet they can lead to clinical depression or mental illness. This literature review looks at the emotional impact on parents and explores how nurses can address this issue in order to support parents more effectively. It identifies key areas that nurses could address that would help alleviate parents’ emotional stress.

Effect of long-term aging on the rheological characteristics and printing performance of lead-free solder pastes used for flip-chip assembly

Stencil printing of solder pastes is a critical stage in the SMT assembly process as a high proportion of the solder-related defects can be attributed to this stage. As the trend towards product miniaturization continues, there is a greater need for better understanding of the rheological behaviour and printing performance of new paste formulations. This fundamental understanding is crucial for achieving the repeatable solder paste deposits from board-to-board and pad-to-pad required for more reliable solder interconnections. The paper concerns a study on the effect of ageing on the rheological characteristics and printing performance of new lead-free solder pastes formulations used for flip-chip assembly applications. The objective is to correlate the rheological characteristics of aged paste samples to their printing performance. The methodology developed can be used for bench-marking new lead-free paste formulations in terms of shelf life, the potential deterioration in rheological characteristics and their printing performance.